Aprendiendo a programar con Python

Aprendiendo a programar con Python

@ProfGastonPerez

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Education #EducationalResource #ProgrammingBooks #CodingForBeginners #PythonCrashCourse #Programación #PythonProgramming

This work highlights the praise received for 'Python Crash Course,' a book that offers an engaging and comprehensive approach to learning programming in Python. Aimed at beginners, it provides a blend of foundational concepts and practical projects, ensuring a hands-on experience. It’s celebrated for its clarity and effectiveness in teaching coding skills.

Aprendiendo a programar con Python

@ProfGastonPerez1 day ago

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PRAISE FOR
PYTHON CRASH COURSE
“It has been interesting to see No Starch Press producing future …

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San Francisco
P Y T H O N C R A S H
COURSE
3RD EDITION
A H a n d s - O n , P r o j e c t - B a…

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PYTHON CRASH COURSE, 3RD EDITION. Copyright © 2023 by Eric Matthes.
All rights reserved. No part o…

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For my father, who always made time to
answer my questions about programming,
and for Ever, who…

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About the Author
Eric Matthes was a high school math and science teacher for 25 years, and
he ta…

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BRIEF CONTENTS
Preface to the Third Edition . . . . . . . . . . . . . . . . . . . . . . . . . . . …

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x Brief Contents
Chapter 18: Getting Started with Django . . . . . . . . . . . . . . . . . . . .…

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CONTENTS IN DETAIL
PREFACE TO THE THIRD EDITION xxvii
ACKNOWLEDGMENTS xxxi
INTRODUCTION xxxiii
…

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xii Contents in Detail
Strings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…

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Contents in Detail xiii
Finding the Length of a List . . . . . . . . . . . . . . . . . . . . . .…

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xiv Contents in Detail
Other Style Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . …

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Contents in Detail xv
Modifying Values in a Dictionary . . . . . . . . . . . . . . . . . . . . .…

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xvi Contents in Detail
Exercise 7-9: No Pastrami . . . . . . . . . . . . . . . . . . . . . . . .…

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Contents in Detail xvii
9
CLASSES 157
Creating and Using a Class . . . . . . . . . . . . . . .…

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xviii Contents in Detail
Working with a File’s Contents . . . . . . . . . . . . . . . . . . . . …

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Contents in Detail xix
Testing a Class . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…

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xx Contents in Detail
Limiting the Number of Bullets . . . . . . . . . . . . . . . . . . . . . .…

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Contents in Detail xxi
Leveling Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .…

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xxii Contents in Detail
Making a Histogram........................................ 322
Customiz…

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Contents in Detail xxiii
17
WORKING WITH APIS 355
Using an API . . . . . . . . . . . . . . . .…

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xxiv Contents in Detail
Exercise 18-5: Meal Planner . . . . . . . . . . . . . . . . . . . . . . …

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Contents in Detail xxv
Creating a requirements.txt File . . . . . . . . . . . . . . . . . . . . …

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xxvi Contents in Detail
Searching Online . . . . . . . . . . . . . . . . . . . . . . . . . . . .…

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PREFACE TO THE THIRD EDITION
The response to the first and second editions of Python Crash Course …

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xxviii Preface to the Third Edition
The following is a summary of specific changes that have bee…

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Preface to the Third Edition xxix
help. Appendix D continues to offer a mini crash course in usi…

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ACKNOWLEDGMENTS
This book would not have been possible without the wonderful and
extremely profe…

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xxxii Acknowledgments
helping newer programmers develop a solid understanding of the Python
la…

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INTRODUCTION
Every programmer has a story about how
they learned to write their first program.
…

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xxxiv Introduction
I’ll always remember how satisfied I felt, watching my family play a
game t…

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Introduction xxxv
so you only have to write blocks of code that perform certain actions once,
…

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xxxvi Introduction
Solutions to exercises You should spend significant time on your own
attemp…

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PART I
BASICS
Part I of this book teaches you the basic concepts you’ll
need to write Python pr…

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2 Part I: Basics
Chapter 10 shows you how to work with files and handle errors so your
progra…

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1
GET TING STARTED
In this chapter, you’ll run your first Python
program, hello_world.py. First…

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4 Chapter 1
Python Versions
Every programming language evolves as new ideas and technologies em…

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Getting Started 5
point. If you want to begin programming quickly, you can use VS Code to
star…

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6 Chapter 1
Figure 1-1: Make sure you select the checkbox labeled
Add Python to PATH.
Running…

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Getting Started 7
Python on macOS
Python is not installed by default on the latest versions of …

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8 Chapter 1
This command starts a Python terminal session. You should see a
Python prompt (>>>…

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Getting Started 9
terminal prompt. Whenever you see the python command in this book, enter
pyt…

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10 Chapter 1
NOTE If you’re using macOS and a pop-up asks you to install the command line devel…

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Getting Started 11
• Step away from your computer, take a short break, and then try again.
Re…

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12 Chapter 1
On Windows
You can use the terminal command cd, for change directory, to navigate …

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Getting Started 13
TRY IT YOURSELF
The exercises in this chapter are exploratory in nature. Sta…

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2
V A R I A B L E S A N D
SIMPLE DATA T YPES
In this chapter you’ll learn about the different …

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16 Chapter 2
When you run the file hello_world.py, the ending .py indicates that the
file is a…

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Variables and Simple Data Types 17
Naming and Using Variables
When you’re using variables in P…

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18 Chapter 2
Here’s an example of the traceback that Python provides after you’ve accidentally …

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Variables and Simple Data Types 19
This distinction probably won’t matter much in your initial …

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20 Chapter 2
Changing Case in a String with Methods
One of the simplest tasks you can do with s…

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Variables and Simple Data Types 21
a last name, respectively, and then combine those values to …

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$22 Chapter 2 To add a tab to your text, use the character combination \t: >>> print("Python") …$

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Variables and Simple Data Types 23
The value associated with favorite_language 1 contains extra…

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24 Chapter 2
Enter the name of the variable followed by a dot, and then the method
removeprefi…

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Variables and Simple Data Types 25
something in the code as valid Python code, and it thinks th…

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26 Chapter 2
Numbers
Numbers are used quite often in programming to keep score in games,
repr…

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Variables and Simple Data Types 27
can appear at any position in a number. Every programming la…

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28 Chapter 2
Python defaults to a float in any operation that uses a float, even if the
output…

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Variables and Simple Data Types 29
TRY IT YOURSELF
2-9. Number Eight: Write addition, subtract…

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30 Chapter 2
forgotten some of the details. You can always study your code for a while
and fig…

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Variables and Simple Data Types 31
someone might look over your shoulder one day and say, “Wow,…

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32 Chapter 2
Summary
In this chapter you learned how to work with variables. You learned to use…

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3
INTRODUCING LISTS
In this chapter and the next you’ll learn
what lists are and how to start w…

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34 Chapter 3
a list usually contains more than one element, it’s a good idea to make the
name …

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Introducing Lists 35
how the list operations are implemented at a lower level. If you’re receivi…

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36 Chapter 3
TRY IT YOURSELF
Try these short programs to get some firsthand experience with Pyt…

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Introducing Lists 37
Here we define the list motorcycles, with 'honda' as the first element.
T…

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38 Chapter 3
Building lists this way is very common, because you often won’t know
the data you…

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Introducing Lists 39
You can remove an item from any position in a list using the del statement…

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40 Chapter 3
How might this pop() method be useful? Imagine that the motorcycles
in the list a…

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Introducing Lists 41
Here the remove() method tells Python to figure out where 'ducati'
appears…

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42 Chapter 3
3-5. Changing Guest List: You just heard that one of your guests can’t make the
d…

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Introducing Lists 43
to preserve the original order of your list, and other times you’ll want to…

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44 Chapter 3
We first print the list in its original order 1 and then in alphabetical
order 2.…

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Introducing Lists 45
You’ll find len() useful when you need to identify the number of aliens
t…

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46 Chapter 3
Avoiding Index Errors When Working with Lists
There’s one type of error that’s com…

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Introducing Lists 47
If an index error occurs and you can’t figure out how to resolve it, try
…

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4
WORKING WITH LISTS
In Chapter 3 you learned how to make a
simple list, and you learned to wor…

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50 Chapter 4
Or perhaps you’ll want to display each headline from a list of articles on a
webs…

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Working with Lists 51
Python prints the current value of magician again, which is now 'david'.
…

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52 Chapter 4
Let’s add a second line to our message, telling each magician that we’re
looking …

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Working with Lists 53
I can't wait to see your next trick, David.
Carolina, that was a great tr…

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54 Chapter 4
You can usually resolve this kind of indentation error by indenting the
line or l…

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Working with Lists 55
You can avoid unexpected indentation errors by indenting only when
you h…

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56 Chapter 4
If you accidentally forget the colon 1, you’ll get a syntax error because
Python …

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Working with Lists 57
to keep track of a player’s high scores as well. In data visualizations, y…

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58 Chapter 4
Using range() to Make a List of Numbers
If you want to make a list of numbers, you…

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Working with Lists 59
To write this code more concisely, omit the temporary variable square
and…

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60 Chapter 4
To use this syntax, begin with a descriptive name for the list, such as
squares. …

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Working with Lists 61
Working with Part of a List
In Chapter 3 you learned how to access single…

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62 Chapter 4
Python returns all items from the third item through the end of the list:
['michae…

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Working with Lists 63
Copying a List
Often, you’ll want to start with an existing list and make…

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64 Chapter 4
We copy the original items in my_foods to the new list friend_foods, as we
did in…

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Working with Lists 65
TRY IT YOURSELF
4-10. Slices: Using one of the programs you wrote in this…

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66 Chapter 4
For example, if we have a rectangle that should always be a certain size, we
can …

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Working with Lists 67
Python returns all the elements in the tuple, just as it would for a list:…

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68 Chapter 4
Styling Your Code
Now that you’re writing longer programs, it’s a good idea to lea…

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Working with Lists 69
Line Length
Many Python programmers recommend that each line should be le…

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70 Chapter 4
TRY IT YOURSELF
4-14. PEP 8: Look through the original PEP 8 style guide at https:…

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5
IF STATEMENTS
Programming often involves examining
a set of conditions and deciding which
a…

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72 Chapter 5
A Simple Example
The following example shows how if tests let you respond to speci…

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if Statements 73
The first line sets the value of car to 'bmw' using a single equal sign, as
y…

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74 Chapter 5
ensure that every user has a truly unique username, not just a variation on
the c…

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if Statements 75
You can include various mathematical comparisons in your conditional
statemen…

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76 Chapter 5
Using or to Check Multiple Conditions
The keyword or allows you to check multiple …

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$if Statements 77 if user not in banned_users: print(f"{user.title()}, you can post a response …$

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78 Chapter 5
5-2. More Conditional Tests: You don’t have to limit the number of tests you creat…

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if Statements 79
Indentation plays the same role in if statements as it did in for loops. All
…

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80 Chapter 5
structure works well in situations in which you want Python to always execute one …

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if Statements 81
and then have a single print() call that runs after the chain has been
evalua…

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82 Chapter 5
Omitting the else Block
Python does not require an else block at the end of an if-…

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if Statements 83
if 'extra cheese' in requested_toppings:
print("Adding extra cheese.")
print…

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84 Chapter 5
TRY IT YOURSELF
5-3. Alien Colors #1: Imagine an alien was just shot down in a gam…

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if Statements 85
5-7. Favorite Fruit: Make a list of your favorite fruits, and then write a seri…

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86 Chapter 5
But what if the pizzeria runs out of green peppers? An if statement
inside the fo…

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if Statements 87
example. If the conditional test fails, we print a message asking the customer…

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88 Chapter 5
In just a few lines of code, we’ve managed a real-world situation pretty
effectiv…

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if Statements 89
Styling Your if Statements
In every example in this chapter, you’ve seen good …

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6
DICTIONARIES
In this chapter you’ll learn how to use
Python’s dictionaries, which allow you t…

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92 Chapter 6
A Simple Dictionary
Consider a game featuring aliens that can have different color…

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Dictionaries 93
This returns the value associated with the key 'color' from the dictionary alie…

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94 Chapter 6
We start by defining the same dictionary that we’ve been working with.
We then pr…

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$Dictionaries 95 alien_0['color'] = 'yellow' print(f"The alien is now {alien_0['color']}.") We …$

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96 Chapter 6
This technique is pretty cool: by changing one value in the alien’s dictionary, yo…

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Dictionaries 97
As you can see, we’ve broken a larger dictionary into several lines. Each
key …

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98 Chapter 6
Let’s see what happens when you ask for the point value of an alien that
doesn’t …

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Dictionaries 99
number for each person, and store each as a value in your dictionary. Print
ea…

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$100 Chapter 6 for key, value in user_0.items(): print(f"\nKey: {key}") print(f"Value: {value…$

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Dictionaries 101
Now, in just a few lines of code, we can display all of the information
from …

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102 Chapter 6
the dictionary as we did previously, but when the name matches one of our
friend…

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Dictionaries 103
One way to do this is to sort the keys as they’re returned in the for loop.
Y…

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104 Chapter 6
This approach pulls all the values from the dictionary without checking for repea…

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Dictionaries 105
6-5. Rivers: Make a dictionary containing three major rivers and the country
…

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106 Chapter 6
We first create three dictionaries, each representing a different alien.
We stor…

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Dictionaries 107
the first three aliens to yellow, medium-speed aliens worth 10 points each,
w…

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108 Chapter 6
on page 99, and store the individual dictionaries in a list called users. All
of…

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Dictionaries 109
When we loop through the dictionary, the value associated with each person wou…

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110 Chapter 6
A Dictionary in a Dictionary
You can nest a dictionary inside another dictionary,…

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Dictionaries 111
Username: mcurie
Full name: Marie Curie
Location: Paris
Notice that the st…

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112 Chapter 6
of the information in a dictionary. You learned to loop through a dictionary’s ke…

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7
USER INPUT AND WHILE LOOPS
Most programs are written to solve an end
user’s problem. To do so…

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114 Chapter 7
program can work with that information. You’ll use Python’s while loop to
keep p…

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User Input and while Loops 115
Sometimes you’ll want to write a prompt that’s longer than one li…

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116 Chapter 7
We can resolve this issue by using the int() function, which converts
the input …

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User Input and while Loops 117
The modulo operator doesn’t tell you how many times one number fi…

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118 Chapter 7
print(current_number)
current_number += 1
In the first line, we start counting…

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User Input and while Loops 119
problem, we make sure to give message an initial value. Although …

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120 Chapter 7
Using a Flag
In the previous example, we had the program perform certain tasks wh…

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User Input and while Loops 121
have a flag to indicate whether the overall program is in an acti…

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122 Chapter 7
Using continue in a Loop
Rather than breaking out of a loop entirely without exec…

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User Input and while Loops 123
Now the value of x will start at 1 but never change. As a result,…

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124 Chapter 7
Using a while Loop with Lists and Dictionaries
So far, we’ve worked with only one…

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User Input and while Loops 125
unconfirmed users is empty, the loop stops and the list of confir…

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126 Chapter 7
while polling_active:
# Prompt for the person's name and response.
1 name = inp…

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User Input and while Loops 127
TRY IT YOURSELF
7-8. Deli: Make a list called sandwich_orders an…

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8
FUNCTIONS
In this chapter you’ll learn to write functions, which are named blocks of code
de…

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130 Chapter 8
Defining a Function
Here’s a simple function named greet_user() that prints a gre…

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Functions 131
Entering greet_user('jesse') calls greet_user() and gives the function the
infor…

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132 Chapter 8
Positional Arguments
When you call a function, Python must match each argument in…

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Functions 133
I have a dog.
My dog's name is Willie.
Calling a function multiple times is a ve…

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134 Chapter 8
The function describe_pet() hasn’t changed. But when we call the function, we exp…

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Functions 135
The simplest way to use this function now is to provide just a dog’s
name in the…

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136 Chapter 8
Avoiding Argument Errors
When you start to use functions, don’t be surprised if y…

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Functions 137
8-4. Large Shirts: Modify the make_shirt() function so that shirts are large
by …

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138 Chapter 8
However, when you consider working with a large program that needs
to store many…

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Functions 139
In this example, the name is built from three possible parts. Because
there’s al…

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140 Chapter 8
This function takes in simple textual information and puts it into a
more meanin…

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Functions 141
inputs? We want the user to be able to quit as easily as possible, so each
promp…

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142 Chapter 8
8-7. Album: Write a function called make_album() that builds a dictionary
descri…

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Functions 143
Modifying a List in a Function
When you pass a list to a function, the function c…

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144 Chapter 8
Move each design to completed_models after printing.
"""
while unprinted_desi…

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Functions 145
print_models() again. If we realize the printing code needs to be modified,
we c…

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146 Chapter 8
TRY IT YOURSELF
8-9. Messages: Make a list containing a series of short text mess…

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$Functions 147 print("\nMaking a pizza with the following toppings:") for topping in toppings:…$

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148 Chapter 8
Making a 12-inch pizza with the following toppings:
- mushrooms
- green peppers
…

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Functions 149
You can mix positional, keyword, and arbitrary values in many different ways when…

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150 Chapter 8
having to share your entire program. Knowing how to import functions
also allows…

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Functions 151
available in your program. If you use this kind of import statement to import
an…

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152 Chapter 8
The general syntax for providing an alias is:
from module_name import function_na…

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Functions 153
Styling Functions
You need to keep a few details in mind when you’re styling func…

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154 Chapter 8
TRY IT YOURSELF
8-15. Printing Models: Put the functions for the example printing…

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Functions 155
Functions also make your code easier to test and debug. When the bulk
of your pr…

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9
CLASSES
Object-oriented programming (OOP) is one of
the most effective approaches to writing …

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158 Chapter 9
less code. You’ll store your classes in modules and import classes written by
ot…

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Classes 159
The __init__() Method
A function that’s part of a class is a method. Everything you…

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160 Chapter 9
Let’s make an instance representing a specific dog:
class Dog:
--snip--
1 my_d…

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Classes 161
To call a method, give the name of the instance (in this case, my_dog)
and the met…

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162 Chapter 9
TRY IT YOURSELF
9-1. Restaurant: Make a class called Restaurant. The __init__() m…

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Classes 163
return long_name.title()
3 my_new_car = Car('audi', 'a4', 2024)
print(my_new_car.…

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164 Chapter 9
This time, when Python calls the __init__() method to create a new
instance, it …

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Classes 165
Here’s an example showing a method called update_odometer():
class Car:
--snip--
…

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166 Chapter 9
on it between the time we buy it and the time we register it. Here’s a
method th…

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Classes 167
Add a method called set_number_served() that lets you set the number of
customers …

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168 Chapter 9
self.year = year
self.odometer_reading = 0
def get_descriptive_name(self):
…

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Classes 169
Aside from __init__(), there are no attributes or methods yet that are
particular …

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170 Chapter 9
electric car to whatever degree of accuracy you need. An attribute or
method tha…

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Classes 171
"""Initialize the battery's attributes."""
self.battery_size = battery_size
2 de…

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172 Chapter 9
add another method to Battery that reports the range of the car based on
the bat…

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Classes 173
logical level rather than a syntax-focused level. You’re thinking not about
Python…

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174 Chapter 9
Importing a Single Class
Let’s create a module containing just the Car class. Thi…

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Classes 175
my_new_car.odometer_reading = 23
my_new_car.read_odometer()
The import statement 1…

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176 Chapter 9
Initialize attributes of the parent class.
Then initialize attributes specific …

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Classes 177
Here’s what it looks like to import the entire car module and then
create a regula…

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178 Chapter 9
class Battery:
--snip--
class ElectricCar(Car):
--snip--
The class ElectricC…

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Classes 179
You can also give a module an alias. Here’s how to import the entire
electric_car …

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180 Chapter 9
One interesting function from the random module is randint(). This
function take…

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Classes 181
Styling Classes
A few styling issues related to classes are worth clarifying, espec…

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10
FILES AND EXCEPTIONS
Now that you’ve mastered the basic skills
you need to write organized p…

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184 Chapter 10
innocent mistakes or from malicious attempts to break your programs. With
the s…

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Files and Exceptions 185
directory as the .py file we’re writing, the filename is all that Path …

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186 Chapter 10
Relative and Absolute File Paths
When you pass a simple filename like pi_digits.…

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Files and Exceptions 187
you might want to modify the text in the file in some way. For example,…

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188 Chapter 10
to hold the digits of pi. We write a loop that adds each line of digits to
pi_s…

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Files and Exceptions 189
The output shows that we do indeed have a string containing pi to
1,0…

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190 Chapter 10
10-2. Learning C: You can use the replace() method to replace any word in a
str…

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Files and Exceptions 191
This file behaves like any other file on your computer. You can open it…

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192 Chapter 10
TRY IT YOURSELF
10-4. Guest: Write a program that prompts the user for their nam…

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Files and Exceptions 193
Using try-except Blocks
When you think an error may occur, you can wri…

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194 Chapter 10
This program prompts the user to input a first_number 1 and, if the
user does n…

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Files and Exceptions 195
we print a friendly message telling the user how to avoid this kind of …

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196 Chapter 10
File "/.../pathlib.py", line 1056, in read_text
with self.open(mode='r', encod…

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Files and Exceptions 197
Let’s pull in the text of Alice in Wonderland and try to count the numb…

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198 Chapter 10
path = Path('alice.txt')
count_words(path)
Most of this code is unchanged. It’s…

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Files and Exceptions 199
nothing in the except block. Python has a pass statement that tells it …

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200 Chapter 10
TRY IT YOURSELF
10-6. Addition: One common problem when prompting for numerical …

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Files and Exceptions 201
Storing Data
Many of your programs will ask users to input certain kin…

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202 Chapter 10
Now we’ll write a separate program that uses json.loads() to read the
list back…

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Files and Exceptions 203
Now let’s write a new program that greets a user whose name has
alrea…

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204 Chapter 10
Otherwise:
Welcome back, Eric!
This is the output you see if the program was al…

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Files and Exceptions 205
if path.exists():
contents = path.read_text()
username = json.load…

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206 Chapter 10
else:
2 username = get_new_username(path)
print(f"We'll remember you when you…

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Files and Exceptions 207
Summary
In this chapter, you learned how to work with files. You learn…

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11
TESTING YOUR CODE
When you write a function or a class, you
can also write tests for that co…

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210 Chapter 11
You’ll learn to build a series of tests and check that each set of inputs
resul…

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Testing Your Code 211
Installing pytest
Now that pip is up to date, we can install pytest:
$ p…

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212 Chapter 11
This program imports get_formatted_name() from name_function.py. The
user can e…

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Testing Your Code 213
Here’s the first test of the function get_formatted_name():
test_name
_f…

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214 Chapter 11
Let’s try to make sense of this output. First of all, we see some information
a…

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Testing Your Code 215
test_name_function.py:5: TypeError
======================= short test sum…

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216 Chapter 11
In this new version of get_formatted_name(), the middle name is optional.
If a …

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Testing Your Code 217
The two dots 1 indicate that two tests passed, which is also clear from
…

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218 Chapter 11
assume is True is actually False, the test will fail and you’ll know there’s an
…

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Testing Your Code 219
have to provide is a question. Once you have an instance representing a pa…

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220 Chapter 11
Implementing such changes would risk affecting the current behavior
of the clas…

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Testing Your Code 221
--snip--
def test_store_three_responses():
"""Test that three individu…

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222 Chapter 11
question = "What language did you first learn to speak?"
language_survey = Ano…

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Testing Your Code 223
decorator to the new function, and add the name of this function as a
pa…

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PART II
PROJECTS
Congratulations! You now know enough about Python
to start building interactiv…

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226 Part II: Projects
and visualize data. Learning to make visualizations allows you to explore…

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12
A SHIP THAT FIRES BULLETS
Let’s build a game called Alien Invasion!
We’ll use Pygame, a coll…

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228 Chapter 12
Making games is an ideal way to have fun while learning a language. It’s
deeply…

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A Ship That Fires Bullets 229
Starting the Game Project
We’ll begin building the game by creati…

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230 Chapter 12
display window to the attribute self.screen, so it will be available in all meth…

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A Ship That Fires Bullets 231
self.clock = pygame.time.Clock()
--snip--
After initializing p…

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232 Chapter 12
mixes equal amounts of red, blue, and green, which produces a light gray
backgr…

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A Ship That Fires Bullets 233
def run_game(self):
--snip--
# Redraw the screen during each …

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234 Chapter 12
Figure 12-1: The ship for Alien Invasion
Creating the Ship Class
After choosing…

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A Ship That Fires Bullets 235
game will notice that we’re not working with the exact shape of ea…

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236 Chapter 12
class AlienInvasion:
"""Overall class to manage game assets and behavior."""
…

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A Ship That Fires Bullets 237
Refactoring: The _check_events() and _update_screen() Methods
In …

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238 Chapter 12
def _update_screen(self):
"""Update images on the screen, and flip to the new …

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A Ship That Fires Bullets 239
When Pygame detects a KEYDOWN event, we need to check whether the …

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240 Chapter 12
# Movement flag; start with a ship that's not moving.
1 self.moving_right = Fal…

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A Ship That Fires Bullets 241
Moving Both Left and Right
Now that the ship can move continuousl…

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242 Chapter 12
Next, we’ll further refine the ship’s movement. Let’s adjust the ship’s
speed a…

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A Ship That Fires Bullets 243
if self.moving_left:
self.x -= self.settings.ship_speed
# Upd…

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244 Chapter 12
When you run alien_invasion.py now, the ship should stop moving at
either edge …

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A Ship That Fires Bullets 245
self.ship.moving_left = True
elif event.key == pygame.K_q:
sy…

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246 Chapter 12
alien_invasion.py
The main file, alien_invasion.py, contains the AlienInvasion c…

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A Ship That Fires Bullets 247
Shooting Bullets
Now let’s add the ability to shoot bullets. We’l…

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248 Chapter 12
super() to inherit properly from Sprite. We also set attributes for the screen
…

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A Ship That Fires Bullets 249
First, we’ll import the new Bullet class:
alien_invasion.py --sni…

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250 Chapter 12
def _update_screen(self):
"""Update images on the screen, and flip to the new …

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A Ship That Fires Bullets 251
We need to get rid of these old bullets, or the game will slow dow…

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252 Chapter 12
This limits the player to three bullets at a time. We’ll use this setting in
Al…

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A Ship That Fires Bullets 253
Run alien_invasion.py one more time, and make sure you can still f…

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13
ALIENS!
In this chapter, we’ll add aliens to Alien
Invasion. We’ll add one alien near the to…

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256 Chapter 13
Reviewing the Project
When you’re beginning a new phase of development on a larg…

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Aliens! 257
Creating the Alien Class
Now we’ll write the Alien class and save it as alien.py:
…

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258 Chapter 13
And here’s the updated __init__() method:
alien_invasion.py def __init__(self):
…

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Aliens! 259
Now that the first alien appears correctly, we’ll write the code to draw
an entire…

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260 Chapter 13
Whenever there’s enough horizontal space to continue the loop, we
want to do tw…

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Aliens! 261
1 def _create_alien(self, x_position):
"""Create an alien and place it in the row.…

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262 Chapter 13
We call _create_alien(), and pass it the y-value as well as its x-position 4.
W…

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Aliens! 263
TRY IT YOURSELF
13-1. Stars: Find an image of a star. Make a grid of stars appear o…

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264 Chapter 13
right by the amount stored in alien_speed. We track the alien’s exact position
…

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Aliens! 265
changes direction. (Using numbers also makes sense because moving right
involves a…

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266 Chapter 13
"""Drop the entire fleet and change the fleet's direction."""
for alien in sel…

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Aliens! 267
Detecting Bullet Collisions
We want to know right away when a bullet hits an alien …

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268 Chapter 13
Making Larger Bullets for Testing
You can test many features of Alien Invasion s…

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Aliens! 269
# Destroy existing bullets and create new fleet.
2 self.bullets.empty()
self._cr…

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270 Chapter 13
if not self.aliens:
# Destroy existing bullets and create new fleet.
self.bu…

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Aliens! 271
If no collisions occur, spritecollideany() returns None and the if block
won’t exe…

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272 Chapter 13
We also need to make a few changes in alien_invasion.py to create an
instance o…

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Aliens! 273
# Pause.
4 sleep(0.5)
The new method _ship_hit() coordinates the response when an…

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274 Chapter 13
1 if alien.rect.bottom >= self.settings.screen_height:
# Treat this the same as…

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Aliens! 275
Most of _ship_hit() is unchanged. We’ve moved all the existing code
into an if blo…

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276 Chapter 13
objects on the screen and to respond to specific situations, such as when the
f…

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14
SCORING
In this chapter, we’ll finish building Alien
Invasion. We’ll add a Play button to st…

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278 Chapter 14
Adding the Play Button
In this section, we’ll add a Play button that appears bef…

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Scoring 279
Next, we prepare a font attribute for rendering text 3. The None argument tells Pyg…

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280 Chapter 14
Because we need only one Play button, we’ll create the button in the
__init__()…

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Scoring 281
Starting the Game
To start a new game when the player clicks Play, add the followin…

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282 Chapter 14
# Get rid of any remaining bullets and aliens.
2 self.bullets.empty()
self.al…

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Scoring 283
Passing False to set_visible() tells Pygame to hide the cursor when the
mouse is o…

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284 Chapter 14
during the game reset when we start a new game. Here’s the __init__()
method for…

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Scoring 285
because when the aliens move faster across the screen, they’ll also come
down the …

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286 Chapter 14
TRY IT YOURSELF
14-3. Challenging Target Practice: Start with your work from Exe…

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Scoring 287
# Prepare the initial score image.
4 self.prep_score()
Because Scoreboard writes …

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288 Chapter 14
Next, we make an instance of Scoreboard in __init__():
alien_invasion.py def __i…

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Scoring 289
Updating the Score as Aliens Are Shot Down
To write a live score onscreen, we updat…

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290 Chapter 14
We call prep_score() after resetting the game stats when starting a new
game. T…

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Scoring 291
def increase_speed(self):
"""Increase speed settings and alien point values."""
…

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292 Chapter 14
commas at appropriate places in the numerical value that’s provided. This
resul…

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Scoring 293
Here’s the prep_high_score() method:
scoreboard.py def prep_high_score(self):
"""…

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294 Chapter 14
The first time you play Alien Invasion, your score will be the high score,
so i…

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Scoring 295
1 self.level_image = self.font.render(level_str, True,
self.text_color, self.setti…

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296 Chapter 14
Figure 14-5: The current level appears just below the current score.
NOTE In som…

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Scoring 297
Next, we need to modify Scoreboard to create a group of ships we can
display. Here…

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298 Chapter 14
To display the ships on the screen, we call draw() on the group, and
Pygame dra…

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Scoring 299
TRY IT YOURSELF
14-5. All-Time High Score: The high score is reset every time a pla…

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15
GENER ATING DATA
Data visualization is the use of visual representations to explore and prese…

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302 Chapter 15
have to be numbers; with the basics you learned in the first part of this
book,…

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Generating Data 303
1 fig, ax = plt.subplots()
ax.plot(squares)
plt.show()
We first import th…

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304 Chapter 15
We’ll use a few of the available customizations to improve this plot’s
readabil…

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Generating Data 305
Correcting the Plot
Now that we can read the chart better, we can see that …

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306 Chapter 15
Using Built-in Styles
Matplotlib has a number of predefined styles available. Th…

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Generating Data 307
To plot a single point, pass the single x- and y-values of the point to
sc…

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308 Chapter 15
Plotting a Series of Points with scatter()
To plot a series of points, we can pa…

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Generating Data 309
plt.style.use('seaborn')
fig, ax = plt.subplots()
2 ax.scatter(x_values, y…

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310 Chapter 15
Almost every element of a chart is customizable, so you can tell Matplotlib
to …

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Generating Data 311
tell pyplot which colormap to use with the cmap argument. This code colors
…

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312 Chapter 15
Random Walks
In this section, we’ll use Python to generate data for a random wal…

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Generating Data 313
# Keep taking steps until the walk reaches the desired length.
1 while len…

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314 Chapter 15
1 rw = RandomWalk()
rw.fill_walk()
# Plot the points in the walk.
plt.style.us…

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Generating Data 315
while True:
# Make a random walk.
--snip--
plt.show()
keep_running =…

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316 Chapter 15
We use range() to generate a list of numbers equal to the number of
points in t…

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Generating Data 317
plot the last x- and y-values in red with a size of 100 as well. Make sure y…

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318 Chapter 15
This example creates a random walk with 50,000 points and plots each
point at s…

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Generating Data 319
TRY IT YOURSELF
15-3. Molecular Motion: Modify rw_visual.py by replacing ax…

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320 Chapter 15
Installing Plotly
Install Plotly using pip, just as you did for Matplotlib:
$ p…

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Generating Data 321
# Make some rolls, and store results in a list.
results = []
2 for roll_nu…

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322 Chapter 15
then append this value to frequencies 4. We print this list before making a
vis…

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Generating Data 323
Figure 15-12: The initial plot produced by Plotly Express
Customizing the P…

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324 Chapter 15
Figure 15-13: A simple bar chart created with Plotly
Rolling Two Dice
Rolling t…

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Generating Data 325
# Visualize the results.
title = "Results of Rolling Two D6 Dice 1,000 Time…

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326 Chapter 15
Plotly has an update_layout() method that can be used to make a wide
variety of…

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Generating Data 327
Figure 15-15 shows the resulting chart. Instead of one most likely result,
…

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328 Chapter 15
TRY IT YOURSELF
15-6. Two D8s: Create a simulation showing what happens when you…

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16
DOWNLOADING DATA
In this chapter, you’ll download datasets
from online sources and create wo…

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330 Chapter 16
By the end of this chapter, you’ll be prepared to work with various types
of da…

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Downloading Data 331
Next, we build a reader object 2. This is an object that can be used
to p…

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332 Chapter 16
We can see that the dates and their high temperatures are stored in columns 2 an…

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Downloading Data 333
# Plot the high temperatures.
plt.style.use('seaborn')
fig, ax = plt.subp…

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334 Chapter 16
an object representing July 1, 2021, using the strptime() method from the
datet…

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Downloading Data 335
reader = csv.reader(lines)
header_row = next(reader)
# Extract dates and …

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336 Chapter 16
Plotting a Longer Timeframe
With our graph set up, let’s include additional data…

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Downloading Data 337
current_date = datetime.strptime(row[2], '%Y-%m-%d')
high = int(row[4])
…

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338 Chapter 16
fig, ax = plt.subplots()
1 ax.plot(dates, highs, color='red', alpha=0.5)
ax.plo…

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Downloading Data 339
First, let’s run the code to see the headers that are included in this
da…

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340 Chapter 16
The traceback tells us that Python can’t process the high temperature for
one o…

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Downloading Data 341
Figure 16-6: Daily high and low temperatures for Death Valley
Many dataset…

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342 Chapter 16
6. On the next page, you can select the kinds of data you want. You can
downloa…

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Downloading Data 343
each one was. Because the data is stored in the GeoJSON format, we’ll work …

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344 Chapter 16
We read the data file as a string, and use json.loads() to convert the
string r…

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Downloading Data 345
]
},
"id": "ak0224bju1jx"
},
The key "properties" contains a lot of…

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346 Chapter 16
Notice how short this code is. The neatly formatted file readable_eq_data
.json …

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Downloading Data 347
lats.append(lat)
print(mags[:10])
print(lons[:5])
print(lats[:5])
We m…

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348 Chapter 16
Figure 16-7: A simple map showing where all the earthquakes in the last 24 hours …

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Downloading Data 349
Figure 16-8: The map now shows the magnitude of all earthquakes in the last…

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350 Chapter 16
We add one more argument, to modify the base map over which the
earthquakes are…

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Downloading Data 351
To make this change, we need to pull a little more data from the file:
eq_…

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352 Chapter 16
illustrates the geological structure of the planet. Plotly offers a wide range
…

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Downloading Data 353
formats, you’ll be able to learn how to work with other data formats more
…

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17
WORKING WITH APIS
In this chapter, you’ll learn how to write
a self-contained program that g…

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356 Chapter 17
easily processed format, such as JSON or CSV. Most apps that use external
data …

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Working with APIs 357
The following snippet shows the first few lines of the response:
{
1 "to…

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358 Chapter 17
# Convert the response object to a dictionary.
5 response_dict = r.json()
# Pro…

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$Working with APIs 359 1 print(f"Total repositories: {response_dict['total_count']}") print(f"Co…$

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360 Chapter 17
GitHub’s API returns a lot of information about each repository: there
are 78 k…

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Working with APIs 361
Summarizing the Top Repositories
When we make a visualization for this da…

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362 Chapter 17
Some interesting projects appear in these results, and it might be worth
lookin…

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Working with APIs 363
Save a copy of the program we’ve been working on as python_repos
_visual.…

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364 Chapter 17
Figure 17-1: The most-starred Python projects on GitHub
Styling the Chart
Plotl…

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Working with APIs 365
Figure 17-2: A title has been added to the main chart, and to each axis as…

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366 Chapter 17
fig.update_layout(title_font_size=28, xaxis_title_font_size=20,
yaxis_title_fon…

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$Working with APIs 367 3 repo_link = f"<a href='{repo_url}'>{repo_name}</a>" repo_links.append(…$

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368 Chapter 17
More About Plotly and the GitHub API
Plotly’s documentation is extensive and wel…

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Working with APIs 369
Everything in this program should look familiar, because we’ve used
it a…

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370 Chapter 17
3 submission_dicts = []
for submission_id in submission_ids[:5]:
# Make a new …

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Working with APIs 371
to the discussion page, and the number of comments the submission current…

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372 Chapter 17
17-3. Testing python_repos.py: In python_repos.py, we printed the value of
stat…

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18
GET TING STARTED WITH DJANGO
As the internet has evolved, the line between
websites and mobi…

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374 Chapter 18
you’ll refine the Learning Log project, and then deploy it to a live server so
…

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Getting Started with Django 375
two lowercase Ls, not two ones). If you use a command such as py…

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376 Chapter 18
NOTE Django releases a new version about every eight months, so you may see a new…

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Getting Started with Django 377
Apply all migrations: admin, auth, contenttypes, sessions
Runn…

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378 Chapter 18
term localhost refers to a server that only processes requests on your system;
…

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Getting Started with Django 379
Starting an App
A Django project is organized as a group of ind…

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380 Chapter 18
3 def __str__(self):
"""Return a string representation of the model."""
retur…

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Getting Started with Django 381
# Default django apps.
'django.contrib.admin',
--snip--
]
…

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382 Chapter 18
Setting Up a Superuser
Django allows you to create a superuser, a user who has a…

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Getting Started with Django 383
To register Topic with the admin site, enter the following:
fro…

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384 Chapter 18
Defining the Entry Model
For a user to record what they’ve been learning about c…

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Getting Started with Django 385
Migrating the Entry Model
Because we’ve added a new model, we n…

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386 Chapter 18
the admin interface if you see only the first part of an entry, rather than the
…

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Getting Started with Django 387
If you know the ID of a particular object, you can use the metho…

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388 Chapter 18
only if the entry is longer than 50 characters. Use the admin site to add an
en…

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Getting Started with Django 389
In the main ll_project folder, open the file urls.py. You should…

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390 Chapter 18
The actual URL pattern is a call to the path() function, which takes
three argu…

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Getting Started with Django 391
access any data provided by the view. Because our view for the h…

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392 Chapter 18
NOTE You might see the following error message:
ModuleNotFoundError: No module n…

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Getting Started with Django 393
</p>
2 {% block content %}{% endblock content %}
The first par…

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394 Chapter 18
is part of learning_logs, so we include learning_logs in the path to the parent
…

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Getting Started with Django 395
The new URL pattern is the word topics, followed by a forward sl…

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396 Chapter 18
1 <ul>
2 {% for topic in topics %}
3 <li>{{ topic.text }}</li>
4 {% empty %}
…

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Getting Started with Django 397
Django to generate a link matching the URL pattern with the name…

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398 Chapter 18
When Django finds a URL that matches this pattern, it calls the view
function t…

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Getting Started with Django 399
<li>There are no entries for this topic yet.</li>
{% endfor %…

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400 Chapter 18
Figure 18-5: The detail page for a single topic, showing all entries for a topic
…

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Getting Started with Django 401
In Chapter 19, you’ll make intuitive, user-friendly pages that a…

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19
USER ACCOUNTS
At the heart of a web application is the ability for any user, anywhere in the …

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404 Chapter 19
Allowing Users to Enter Data
Before we build an authentication system for creati…

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User Accounts 405
The new_topic URL
The URL for a new page should be short and descriptive. Whe…

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406 Chapter 19
GET and POST Requests
The two main types of requests you’ll use when building ap…

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User Accounts 407
The new_topic Template
Now we’ll make a new template called new_topic.html to…

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408 Chapter 19
Place the link after the list of existing topics. Figure 19-1 shows the
resulti…

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User Accounts 409
default widget choices. Here we’re telling Django to use a forms.Textarea ele…

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410 Chapter 19
We update the import statement to include the EntryForm we just made.
The defin…

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User Accounts 411
The form’s action argument includes the topic.id value in the URL,
so the vi…

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412 Chapter 19
Editing Entries
Now we’ll make a page so users can edit the entries they’ve adde…

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User Accounts 413
block, which runs for a GET request, we make an instance of EntryForm with
t…

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$414 Chapter 19 <p>{{ entry.date_added|date:'M d, Y H:i' }}</p> <p>{{ entry.text|linebreaks }}…$

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User Accounts 415
TRY IT YOURSELF
19-1. Blog: Start a new Django project called Blog. Create an…

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416 Chapter 19
# Default django apps.
--snip--
]
--snip--
Now Django will include the acco…

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User Accounts 417
The login page’s pattern matches the URL http://localhost:8000/accounts/
logi…

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418 Chapter 19
Add the following code to the end of settings.py:
settings.py --snip--
# My set…

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User Accounts 419
Figure 19-4: The login page
Logging Out
Now we need to provide a way for use…

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420 Chapter 19
consistent position below any other content on the page. The form itself has
th…

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User Accounts 421
The register() View Function
The register() view function needs to display a …

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422 Chapter 19
where a personalized greeting in the header tells them their registration
was s…

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User Accounts 423
NOTE The registration system we’ve set up allows anyone to make any number of …

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424 Chapter 19
We first import the login_required() function. We apply login_required()
as a de…

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User Accounts 425
@login_required
def new_entry(request, topic_id):
--snip--
@login_required…

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426 Chapter 19
Identifying Existing Users
When we migrate the database, Django will modify the …

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User Accounts 427
We start by issuing the makemigrations command 1. In the output,
Django indi…

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428 Chapter 19
Make the following change to the topics() function in views.py:
learning_logs/
…

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User Accounts 429
A 404 response is a standard error response that’s returned when a
requested…

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430 Chapter 19
1 new_topic = form.save(commit=False)
2 new_topic.owner = request.user
3 new_to…

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User Accounts 431
After building a simple user authentication and registration system, you
res…

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20
S T Y L I N G A N D D E P L O Y I N G
AN APP
Learning Log is fully functional now, but
it …

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434 Chapter 20
When you’re finished with Learning Log, you’ll be able to develop
simple web ap…

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Styling and Deploying an App 435
templates Bootstrap offers, go to https://getbootstrap.com and…

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436 Chapter 20
We first declare this file as an HTML document 1 written in English 2.
An HTML …

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Styling and Deploying an App 437
8 {% block content %}{% endblock content %}
</body>
</html>
…

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438 Chapter 20
Closing tags don’t usually have comments, but if you’re new to HTML,
it can be …

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Styling and Deploying an App 439
be confusing at first, because many pages have deeply nested d…

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440 Chapter 20
3 <div>
{% block content %}{% endblock content %}
</div>
</main>
</body>
…

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Styling and Deploying an App 441
5 <a class="btn btn-primary btn-lg mt-1"
href="{% url 'accou…

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$442 Chapter 20 <form action="{% url 'accounts:login' %}" method='post'> {% csrf_token %} 3 {…$

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$Styling and Deploying an App 443 1 <h1>Topics</h1> {% endblock page_header %} {% block conten…$

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$444 Chapter 20 {% block content %} <p> <a href="{% url 'learning_logs:new_entry' topic.id %}…$

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Styling and Deploying an App 445
Figure 20-3: The topic page with Bootstrap styling
TRY IT YOU…

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446 Chapter 20
NOTE The specific limits of trial plans tend to change periodically, as hosting p…

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Styling and Deploying an App 447
django-bootstrap5==21.3
platformshconfig==2.4.0
soupsieve==2…

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448 Chapter 20
These are all YAML (YAML Ain’t Markup Language) files. YAML is
a language desig…

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Styling and Deploying an App 449
root: "static"
expires: 1h
allow: true
# The size of the…

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450 Chapter 20
The mounts section 1 lets us define directories where we can read and
write dat…

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Styling and Deploying an App 451
Modifying settings.py for Platform.sh
Now we need to add a se…

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452 Chapter 20
the last working snapshot of your project; for example, if you accidentally
int…

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Styling and Deploying an App 453
NOTE If you’re using macOS, add .DS_Store to your .gitignore f…

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454 Chapter 20
This command will open a browser tab where you can log in. Once
you’re logged i…

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Styling and Deploying an App 455
The Platform.sh Bot is activating your project
▀▄ ▄▀
█▄█▀█…

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456 Chapter 20
Viewing the Live Project
Once the push is complete, you can open the project:
(…

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Styling and Deploying an App 457
Password:
Password (again):
Superuser created successfully.
…

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458 Chapter 20
Open settings.py in your text editor, and add one line of code to the part
that…

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Styling and Deploying an App 459
To make sure this change took effect, visit the /topics/999/ U…

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460 Chapter 20
This change tells Django to look in the root template directory for the
error p…

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Styling and Deploying an App 461
Deleting a Project on Platform.sh
It’s great practice to run …

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462 Chapter 20
20-4. Extended Learning Log: Add one feature to Learning Log, and push the
chan…

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A
I N S T A L L A T I O N A N D
TROUBLESHOOTING
There are many versions of Python available an…

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464 Appendix A
When Windows doesn’t recognize the python command, it will either open
the Micr…

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Installation and Troubleshooting 465
will then point to the newer version. Don’t worry about hav…

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466 Appendix A
You’ll need to install two more packages to make the most of your Python
instal…

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Installation and Troubleshooting 467
Python Built-in Functions
You won’t get an error if you us…

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B
TEXT EDITORS AND IDES
Programmers spend a lot of time writing,
reading, and editing code, and…

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470 Appendix B
also be overwhelming as a beginner and difficult to troubleshoot when you
aren’…

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Text Editors and IDEs 471
changes in configuration files. These changes will sometimes take effe…

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472 Appendix B
Editor: Rulers; click the link labeled Edit in settings.json. In the file that
…

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Text Editors and IDEs 473
Exploring Further Customizations
You can customize VS Code in many wa…

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474 Appendix B
Finding Additional Shortcuts
Working efficiently in an editing environment takes…

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Text Editors and IDEs 475
Emacs and Vim
Emacs and Vim are two popular editors favored by many e…

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C
GETTING HELP
Everyone gets stuck at some point when
they’re learning to program. So, one of
…

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478 Appendix C
Make your answers as specific as possible. For the first question, explicit
sta…

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Getting Help 479
Searching Online
Chances are good that someone else has had the same problem y…

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480 Appendix C
language than to provide explanations. The examples in the official documentatio…

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Getting Help 481
Slack
Slack is another online chat environment. It is often used for internal …

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D
U S I N G G I T F O R
VERSION CONTROL
Version control software allows you to take
snapshots…

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484 Appendix D
Installing Git
Git runs on all operating systems, but there are different approa…

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Using Git for Version Control 485
called __pycache__. To tell Git to ignore this directory, mak…

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486 Appendix D
In Git, a branch is a version of the project you’re working on; here you
can se…

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Using Git for Version Control 487
project.) in the project’s log. The output shows that we’re o…

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488 Appendix D
2 modified: hello_git.py
3 no changes added to commit (use "git add" and/or "git…

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Using Git for Version Control 489
Git sees that we modified hello_git.py 1, and we can commit t…

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490 Appendix D
If you want to create a new branch to retain commits you create, you may
do so (…

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Using Git for Version Control 491
the commit we want to go back to permanently 3. We check the …

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492 Appendix D
folder, we’re told that this is not a Git repository 3. All the information Git
…

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E
T R O U B L E S H O O T I N G
DEPLOYMENTS
Deploying an app is tremendously satisfying when i…

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494 Appendix E
Understanding Deployments
When you’re trying to troubleshoot a particular deploy…

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Troubleshooting Deployments 495
able to figure out what to change in your project, or in your de…

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496 Appendix E
You should be careful about running commands that you don’t fully
understand. H…

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Troubleshooting Deployments 497
Sometimes, you’ll be able to spot the error, and other times, yo…

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498 Appendix E
One of the most significant difficulties in deploying from Windows is
that the …

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Troubleshooting Deployments 499
click Run as administrator. In the terminal that appears, enter …

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500 Appendix E
The actual output will have more information about a few other packages that wou…

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Troubleshooting Deployments 501
know what works well with your provider’s approach and what does…

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INDEX
Symbols
+ (addition), 26
+= (addition in place), 122
* (arbitrary arguments), 146
** (ar…

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504 Index
drawing, 279–280
hiding mouse cursor, 282–283
resetting game, 281–282
starting game…

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Index 505
comma-separated value files. See CSV files
comment.py, 29
comments, 29–30
condition…

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506 Index
databases
cascading delete, 384
creating, 376
foreign keys, 384, 425
many-to-one r…

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Index 507
settings
ALLOWED_HOSTS, 451
DEBUG, 457–458
INSTALLED_APPS, 380–381,
415–416, 434
…

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508 Index
lists as, 142–145
optional, 138–139
positional, 131–133
body, 130
built-in, 467
c…

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Index 509
insert() method, 38
itemgetter() function, 370
items() method, 99–101
J
JSON files…

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510 Index
errors
indentation, 53–56
index, 46
for loops, 49–56
nested, 108–109, 261–262
ind…

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Index 511
N
name errors, 17–18
name_function.py, 211–217
name.py, 20
names.py, 211–212
nest…

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512 Index
displaying text, 278–280
ending games, 274–275
event loops, 229–230
frame rates, 23…

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Index 513
S
scatter_squares.py, 306–311
sets, 103–104
sitka_highs_lows.py, 336–338
sitka_hig…

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514 Index
unit tests, 212
user_profile.py, 148–149
V
values() method, 103–104
variables, 16–…

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NO STARCH PRESS
phone:
800.420.7240 or
415.863.9900
email:
sales@nostarch.com
web:
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@ProfGastonPerez

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- @ProfGastonPerez
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Material Basico para comenzar con programación de la buena. Python es uno de los lenguajes mas usados en todos los ambitos.

Aprendiendo a programar con Python

@ProfGastonPerez

This work highlights the praise received for 'Python Crash Course,' a book that offers an engaging and comprehensive approach to learning programming in Python. Aimed at beginners, it provides a blend of foundational concepts and practical projects, ensuring a hands-on experience. It’s celebrated for its clarity and effectiveness in teaching coding skills.

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