Python Crash Course

Cover
Praise for Python Crash Course
Copyright
Dedication
About the Author and Technical Reviewer
Brief Contents
Contents in Detail
Preface to the Third Edition
Acknowledgments
Introduction
	Who Is This Book For?
	What Can You Expect to Learn?
	Online Resources
	Why Python?
Part I: Basics
	Chapter 1: Getting Started
		Setting Up Your Programming Environment
			Python Versions
			Running Snippets of Python Code
			About the VS Code Editor
		Python on Different Operating Systems
			Python on Windows
			Python on macOS
			Python on Linux
		Running a Hello World Program
			Installing the Python Extension for VS Code
			Running hello_world.py
		Troubleshooting
		Running Python Programs from a Terminal
			On Windows
			On macOS and Linux
			Exercise 1-1: python.org
			Exercise 1-2: Hello World Typos
			Exercise 1-3: Infinite Skills
		Summary
	Chapter 2: Variables and Simple Data Types
		What Really Happens When You Run hello_world.py
		Variables
			Naming and Using Variables
			Avoiding Name Errors When Using Variables
			Variables Are Labels
			Exercise 2-1: Simple Message
			Exercise 2-2: Simple Messages
		Strings
			Changing Case in a String with Methods
			Using Variables in Strings
			Adding Whitespace to Strings with Tabs or Newlines
			Stripping Whitespace
			Removing Prefixes
			Avoiding Syntax Errors with Strings
			Exercise 2-3: Personal Message
			Exercise 2-4: Name Cases
			Exercise 2-5: Famous Quote
			Exercise 2-6: Famous Quote 2
			Exercise 2-7: Stripping Names
			Exercise 2-8: File Extensions
		Numbers
			Integers
			Floats
			Integers and Floats
			Underscores in Numbers
			Multiple Assignment
			Constants
			Exercise 2-9: Number Eight
			Exercise 2-10: Favorite Number
		Comments
			How Do You Write Comments?
			What Kinds of Comments Should You Write?
			Exercise 2-11: Adding Comments
		The Zen of Python
			Exercise 2-12: Zen of Python
		Summary
	Chapter 3: Introducing Lists
		What Is a List?
			Accessing Elements in a List
			Index Positions Start at 0, Not 1
			Using Individual Values from a List
			Exercise 3-1: Names
			Exercise 3-2: Greetings
			Exercise 3-3: Your Own List
		Modifying, Adding, and Removing Elements
			Modifying Elements in a List
			Adding Elements to a List
			Removing Elements from a List
			Exercise 3-4: Guest List
			Exercise 3-5: Changing Guest List
			Exercise 3-6: More Guests
			Exercise 3-7: Shrinking Guest List
		Organizing a List
			Sorting a List Permanently with the sort() Method
			Sorting a List Temporarily with the sorted() Function
			Printing a List in Reverse Order
			Finding the Length of a List
			Exercise 3-8: Seeing the World
			Exercise 3-9: Dinner Guests
			Exercise 3-10: Every Function
		Avoiding Index Errors When Working with Lists
			Exercise 3-11: Intentional Error
		Summary
	Chapter 4: Working with Lists
		Looping Through an Entire List
			A Closer Look at Looping
			Doing More Work Within a for Loop
			Doing Something After a for Loop
		Avoiding Indentation Errors
			Forgetting to Indent
			Forgetting to Indent Additional Lines
			Indenting Unnecessarily
			Indenting Unnecessarily After the Loop
			Forgetting the Colon
			Exercise 4-1: Pizzas
			Exercise 4-2: Animals
		Making Numerical Lists
			Using the range() Function
			Using range() to Make a List of Numbers
			Simple Statistics with a List of Numbers
			List Comprehensions
			Exercise 4-3: Counting to Twenty
			Exercise 4-4: One Million
			Exercise 4-5: Summing a Million
			Exercise 4-6: Odd Numbers
			Exercise 4-7: Threes
			Exercise 4-8: Cubes
			Exercise 4-9: Cube Comprehension
		Working with Part of a List
			Slicing a List
			Looping Through a Slice
			Copying a List
			Exercise 4-10: Slices
			Exercise 4-11: My Pizzas, Your Pizzas
			Exercise 4-12: More Loops
		Tuples
			Defining a Tuple
			Looping Through All Values in a Tuple
			Writing Over a Tuple
			Exercise 4-13: Buffet
		Styling Your Code
			The Style Guide
			Indentation
			Line Length
			Blank Lines
			Other Style Guidelines
			Exercise 4-14: PEP 8
			Exercise 4-15: Code Review
		Summary
	Chapter 5: if Statements
		A Simple Example
		Conditional Tests
			Checking for Equality
			Ignoring Case When Checking for Equality
			Checking for Inequality
			Numerical Comparisons
			Checking Multiple Conditions
			Checking Whether a Value Is in a List
			Checking Whether a Value Is Not in a List
			Boolean Expressions
			Exercise 5-1: Conditional Tests
			Exercise 5-2: More Conditional Tests
		if Statements
			Simple if Statements
			if-else Statements
			The if-elif-else Chain
			Using Multiple elif Blocks
			Omitting the else Block
			Testing Multiple Conditions
			Exercise 5-3: Alien Colors #1
			Exercise 5-4: Alien Colors #2
			Exercise 5-5: Alien Colors #3
			Exercise 5-6: Stages of Life
			Exercise 5-7: Favorite Fruit
		Using if Statements with Lists
			Checking for Special Items
			Checking That a List Is Not Empty
			Using Multiple Lists
			Exercise 5-8: Hello Admin
			Exercise 5-9: No Users
			Exercise 5-10: Checking Usernames
			Exercise 5-11: Ordinal Numbers
		Styling Your if Statements
			Exercise 5-12: Styling if Statements
			Exercise 5-13: Your Ideas
		Summary
	Chapter 6: Dictionaries
		A Simple Dictionary
		Working with Dictionaries
			Accessing Values in a Dictionary
			Adding New Key-Value Pairs
			Starting with an Empty Dictionary
			Modifying Values in a Dictionary
			Removing Key-Value Pairs
			A Dictionary of Similar Objects
			Using get() to Access Values
			Exercise 6-1: Person
			Exercise 6-2: Favorite Numbers
			Exercise 6-3: Glossary
		Looping Through a Dictionary
			Looping Through All Key-Value Pairs
			Looping Through All the Keys in a Dictionary
			Looping Through a Dictionary’s Keys in a Particular Order
			Looping Through All Values in a Dictionary
			Exercise 6-4: Glossary 2
			Exercise 6-5: Rivers
			Exercise 6-6: Polling
		Nesting
			A List of Dictionaries
			A List in a Dictionary
			A Dictionary in a Dictionary
			Exercise 6-7: People
			Exercise 6-8: Pets
			Exercise 6-9: Favorite Places
			Exercise 6-10: Favorite Numbers
			Exercise 6-11: Cities
			Exercise 6-12: Extensions
		Summary
	Chapter 7: User Input and while Loops
		How the input() Function Works
			Writing Clear Prompts
			Using int() to Accept Numerical Input
			The Modulo Operator
			Exercise 7-1: Rental Car
			Exercise 7-2: Restaurant Seating
			Exercise 7-3: Multiples of Ten
		Introducing while Loops
			The while Loop in Action
			Letting the User Choose When to Quit
			Using a Flag
			Using break to Exit a Loop
			Using continue in a Loop
			Avoiding Infinite Loops
			Exercise 7-4: Pizza Toppings
			Exercise 7-5: Movie Tickets
			Exercise 7-6: Three Exits
			Exercise 7-7: Infinity
		Using a while Loop with Lists and Dictionaries
			Moving Items from One List to Another
			Removing All Instances of Specific Values from a List
			Filling a Dictionary with User Input
			Exercise 7-8: Deli
			Exercise 7-9: No Pastrami
			Exercise 7-10: Dream Vacation
		Summary
	Chapter 8: Functions
		Defining a Function
			Passing Information to a Function
			Arguments and Parameters
			Exercise 8-1: Message
			Exercise 8-2: Favorite Book
		Passing Arguments
			Positional Arguments
			Keyword Arguments
			Default Values
			Equivalent Function Calls
			Avoiding Argument Errors
			Exercise 8-3: T-Shirt
			Exercise 8-4: Large Shirts
			Exercise 8-5: Cities
		Return Values
			Returning a Simple Value
			Making an Argument Optional
			Returning a Dictionary
			Using a Function with a while Loop
			Exercise 8-6: City Names
			Exercise 8-7: Album
			Exercise 8-8: User Albums
		Passing a List
			Modifying a List in a Function
			Preventing a Function from Modifying a List
			Exercise 8-9: Messages
			Exercise 8-10: Sending Messages
			Exercise 8-11: Archived Messages
		Passing an Arbitrary Number of Arguments
			Mixing Positional and Arbitrary Arguments
			Using Arbitrary Keyword Arguments
			Exercise 8-12: Sandwiches
			Exercise 8-13: User Profile
			Exercise 8-14: Cars
		Storing Your Functions in Modules
			Importing an Entire Module
			Importing Specific Functions
			Using as to Give a Function an Alias
			Using as to Give a Module an Alias
			Importing All Functions in a Module
		Styling Functions
			Exercise 8-15: Printing Models
			Exercise 8-16: Imports
			Exercise 8-17: Styling Functions
		Summary
	Chapter 9: Classes
		Creating and Using a Class
			Creating the Dog Class
			The __init__() Method
			Making an Instance from a Class
			Exercise 9-1: Restaurant
			Exercise 9-2: Three Restaurants
			Exercise 9-3: Users
		Working with Classes and Instances
			The Car Class
			Setting a Default Value for an Attribute
			Modifying Attribute Values
			Exercise 9-4: Number Served
			Exercise 9-5: Login Attempts
		Inheritance
			The __init__() Method for a Child Class
			Defining Attributes and Methods for the Child Class
			Overriding Methods from the Parent Class
			Instances as Attributes
			Modeling Real-World Objects
			Exercise 9-6: Ice Cream Stand
			Exercise 9-7: Admin
			Exercise 9-8: Privileges
			Exercise 9-9: Battery Upgrade
		Importing Classes
			Importing a Single Class
			Storing Multiple Classes in a Module
			Importing Multiple Classes from a Module
			Importing an Entire Module
			Importing All Classes from a Module
			Importing a Module into a Module
			Using Aliases
			Finding Your Own Workflow
			Exercise 9-10: Imported Restaurant
			Exercise 9-11: Imported Admin
			Exercise 9-12: Multiple Modules
		The Python Standard Library
			Exercise 9-13: Dice
			Exercise 9-14: Lottery
			Exercise 9-15: Lottery Analysis
			Exercise 9-16: Python Module of the Week
		Styling Classes
		Summary
	Chapter 10: Files and Exceptions
		Reading from a File
			Reading the Contents of a File
			Relative and Absolute File Paths
			Accessing a File’s Lines
			Working with a File’s Contents
			Large Files: One Million Digits
			Is Your Birthday Contained in Pi?
			Exercise 10-1: Learning Python
			Exercise 10-2: Learning C
			Exercise 10-3: Simpler Code
		Writing to a File
			Writing a Single Line
			Writing Multiple Lines
			Exercise 10-4: Guest
			Exercise 10-5: Guest Book
		Exceptions
			Handling the ZeroDivisionError Exception
			Using try-except Blocks
			Using Exceptions to Prevent Crashes
			The else Block
			Handling the FileNotFoundError Exception
			Analyzing Text
			Working with Multiple Files
			Failing Silently
			Deciding Which Errors to Report
			Exercise 10-6: Addition
			Exercise 10-7: Addition Calculator
			Exercise 10-8: Cats and Dogs
			Exercise 10-9: Silent Cats and Dogs
			Exercise 10-10: Common Words
		Storing Data
			Using json.dumps() and json.loads()
			Saving and Reading User-Generated Data
			Refactoring
			Exercise 10-11: Favorite Number
			Exercise 10-12: Favorite Number Remembered
			Exercise 10-13: User Dictionary
			Exercise 10-14: Verify User
		Summary
	Chapter 11: Testing Your Code
		Installing pytest with pip
			Updating pip
			Installing pytest
		Testing a Function
			Unit Tests and Test Cases
			A Passing Test
			Running a Test
			A Failing Test
			Responding to a Failed Test
			Adding New Tests
			Exercise 11-1: City, Country
			Exercise 11-2: Population
		Testing a Class
			A Variety of Assertions
			A Class to Test
			Testing the AnonymousSurvey Class
			Using Fixtures
			Exercise 11-3: Employee
		Summary
Part II: Projects
	Chapter 12: A Ship That Fires Bullets
		Planning Your Project
		Installing Pygame
		Starting the Game Project
			Creating a Pygame Window and Responding to User Input
			Controlling the Frame Rate
			Setting the Background Color
			Creating a Settings Class
		Adding the Ship Image
			Creating the Ship Class
			Drawing the Ship to the Screen
		Refactoring: The _check_events() and _update_screen() Methods
			The _check_events() Method
			The _update_screen() Method
			Exercise 12-1: Blue Sky
			Exercise 12-2: Game Character
		Piloting the Ship
			Responding to a Keypress
			Allowing Continuous Movement
			Moving Both Left and Right
			Adjusting the Ship’s Speed
			Limiting the Ship’s Range
			Refactoring _check_events()
			Pressing Q to Quit
			Running the Game in Fullscreen Mode
		A Quick Recap
			alien_invasion.py
			settings.py
			ship.py
			Exercise 12-3: Pygame Documentation
			Exercise 12-4: Rocket
			Exercise 12-5: Keys
		Shooting Bullets
			Adding the Bullet Settings
			Creating the Bullet Class
			Storing Bullets in a Group
			Firing Bullets
			Deleting Old Bullets
			Limiting the Number of Bullets
			Creating the _update_bullets() Method
			Exercise 12-6: Sideways Shooter
		Summary
	Chapter 13: Aliens!
		Reviewing the Project
		Creating the First Alien
			Creating the Alien Class
			Creating an Instance of the Alien
		Building the Alien Fleet
			Creating a Row of Aliens
			Refactoring _create_fleet()
			Adding Rows
			Exercise 13-1: Stars
			Exercise 13-2: Better Stars
		Making the Fleet Move
			Moving the Aliens Right
			Creating Settings for Fleet Direction
			Checking Whether an Alien Has Hit the Edge
			Dropping the Fleet and Changing Direction
			Exercise 13-3: Raindrops
			Exercise 13-4: Steady Rain
		Shooting Aliens
			Detecting Bullet Collisions
			Making Larger Bullets for Testing
			Repopulating the Fleet
			Speeding Up the Bullets
			Refactoring _update_bullets()
			Exercise 13-5: Sideways Shooter Part 2
		Ending the Game
			Detecting Alien-Ship Collisions
			Responding to Alien-Ship Collisions
			Aliens That Reach the Bottom of the Screen
			Game Over!
			Identifying When Parts of the Game Should Run
			Exercise 13-6: Game Over
		Summary
	Chapter 14: Scoring
		Adding the Play Button
			Creating a Button Class
			Drawing the Button to the Screen
			Starting the Game
			Resetting the Game
			Deactivating the Play Button
			Hiding the Mouse Cursor
			Exercise 14-1: Press P to Play
			Exercise 14-2: Target Practice
		Leveling Up
			Modifying the Speed Settings
			Resetting the Speed
			Exercise 14-3: Challenging Target Practice
			Exercise 14-4: Difficulty Levels
		Scoring
			Displaying the Score
			Making a Scoreboard
			Updating the Score as Aliens Are Shot Down
			Resetting the Score
			Making Sure to Score All Hits
			Increasing Point Values
			Rounding the Score
			High Scores
			Displaying the Level
			Displaying the Number of Ships
			Exercise 14-5: All-Time High Score
			Exercise 14-6: Refactoring
			Exercise 14-7: Expanding the Game
			Exercise 14-8: Sideways Shooter, Final Version
		Summary
	Chapter 15: Generating Data
		Installing Matplotlib
		Plotting a Simple Line Graph
			Changing the Label Type and Line Thickness
			Correcting the Plot
			Using Built-in Styles
			Plotting and Styling Individual Points with scatter()
			Plotting a Series of Points with scatter()
			Calculating Data Automatically
			Customizing Tick Labels
			Defining Custom Colors
			Using a Colormap
			Saving Your Plots Automatically
			Exercise 15-1. Cubes
			Exercise 15-2: Colored Cubes
		Random Walks
			Creating the RandomWalk Class
			Choosing Directions
			Plotting the Random Walk
			Generating Multiple Random Walks
			Styling the Walk
			Exercise 15-3: Molecular Motion
			Exercise 15-4: Modified Random Walks
			Exercise 15-5: Refactoring
		Rolling Dice with Plotly
			Installing Plotly
			Creating the Die Class
			Rolling the Die
			Analyzing the Results
			Making a Histogram
			Customizing the Plot
			Rolling Two Dice
			Further Customizations
			Rolling Dice of Different Sizes
			Saving Figures
			Exercise 15-6: Two D8s
			Exercise 15-7: Three Dice
			Exercise 15-8: Multiplication
			Exercise 15-9: Die Comprehensions
			Exercise 15-10: Practicing with Both Libraries
		Summary
	Chapter 16: Downloading Data
		The CSV File Format
			Parsing the CSV File Headers
			Printing the Headers and Their Positions
			Extracting and Reading Data
			Plotting Data in a Temperature Chart
			The datetime Module
			Plotting Dates
			Plotting a Longer Timeframe
			Plotting a Second Data Series
			Shading an Area in the Chart
			Error Checking
			Downloading Your Own Data
			Exercise 16-1: Sitka Rainfall
			Exercise 16-2: Sitka–Death Valley Comparison
			Exercise 16-3: San Francisco
			Exercise 16-4: Automatic Indexes
			Exercise 16-5: Explore
		Mapping Global Datasets: GeoJSON Format
			Downloading Earthquake Data
			Examining GeoJSON Data
			Making a List of All Earthquakes
			Extracting Magnitudes
			Extracting Location Data
			Building a World Map
			Representing Magnitudes
			Customizing Marker Colors
			Other Color Scales
			Adding Hover Text
			Exercise 16-6: Refactoring
			Exercise 16-7: Automated Title
			Exercise 16-8: Recent Earthquakes
			Exercise 16-9: World Fires
		Summary
	Chapter 17: Working with APIs
		Using an API
			Git and GitHub
			Requesting Data Using an API Call
			Installing Requests
			Processing an API Response
			Working with the Response Dictionary
			Summarizing the Top Repositories
			Monitoring API Rate Limits
		Visualizing Repositories Using Plotly
			Styling the Chart
			Adding Custom Tooltips
			Adding Clickable Links
			Customizing Marker Colors
			More About Plotly and the GitHub API
		The Hacker News API
			Exercise 17-1: Other Languages
			Exercise 17-2: Active Discussions
			Exercise 17-3: Testing python_repos.py
			Exercise 17-4: Further Exploration
		Summary
	Chapter 18: Getting Started with Django
		Setting Up a Project
			Writing a Spec
			Creating a Virtual Environment
			Activating the Virtual Environment
			Installing Django
			Creating a Project in Django
			Creating the Database
			Viewing the Project
			Exercise 18-1: New Projects
		Starting an App
			Defining Models
			Activating Models
			The Django Admin Site
			Defining the Entry Model
			Migrating the Entry Model
			Registering Entry with the Admin Site
			The Django Shell
			Exercise 18-2: Short Entries
			Exercise 18-3: The Django API
			Exercise 18-4: Pizzeria
		Making Pages: The Learning Log Home Page
			Mapping a URL
			Writing a View
			Writing a Template
			Exercise 18-5: Meal Planner
			Exercise 18-6: Pizzeria Home Page
		Building Additional Pages
			Template Inheritance
			The Topics Page
			Individual Topic Pages
			Exercise 18-7: Template Documentation
			Exercise 18-8: Pizzeria Pages
		Summary
	Chapter 19: User Accounts
		Allowing Users to Enter Data
			Adding New Topics
			Adding New Entries
			Editing Entries
			Exercise 19-1: Blog
		Setting Up User Accounts
			The accounts App
			The Login Page
			Logging Out
			The Registration Page
			Exercise 19-2: Blog Accounts
		Allowing Users to Own Their Data
			Restricting Access with @login_required
			Connecting Data to Certain Users
			Restricting Topics Access to Appropriate Users
			Protecting a User’s Topics
			Protecting the edit_entry Page
			Associating New Topics with the Current User
			Exercise 19-3: Refactoring
			Exercise 19-4: Protecting new_entry
			Exercise 19-5: Protected Blog
		Summary
	Chapter 20: Styling and Deploying an App
		Styling Learning Log
			The django-bootstrap5 App
			Using Bootstrap to Style Learning Log
			Modifying base.html
			Styling the Home Page Using a Jumbotron
			Styling the Login Page
			Styling the Topics Page
			Styling the Entries on the Topic Page
			Exercise 20-1: Other Forms
			Exercise 20-2: Stylish Blog
		Deploying Learning Log
			Making a Platform.sh Account
			Installing the Platform.sh CLI
			Installing platformshconfig
			Creating a requirements.txt File
			Additional Deployment Requirements
			Adding Configuration Files
			Modifying settings.py for Platform.sh
			Using Git to Track the Project’s Files
			Creating a Project on Platform.sh
			Pushing to Platform.sh
			Viewing the Live Project
			Refining the Platform.sh Deployment
			Creating Custom Error Pages
			Ongoing Development
			Deleting a Project on Platform.sh
			Exercise 20-3: Live Blog
			Exercise 20-4: Extended Learning Log
		Summary
	Appendix A: Installation and Troubleshooting
		Python on Windows
			Using py Instead of python
			Rerunning the Installer
		Python on macOS
			Accidentally Installing Apple’s Version of Python
			Python 2 on Older Versions of macOS
		Python on Linux
			Using the Default Python Installation
			Installing the Latest Version of Python
		Checking Which Version of Python You’re Using
		Python Keywords and Built-in Functions
			Python Keywords
			Python Built-in Functions
	Appendix B: Text Editors and IDEs
		Working Efficiently with VS Code
			Configuring VS Code
			VS Code Shortcuts
		Other Text Editors and IDEs
			IDLE
			Geany
			Sublime Text
			Emacs and Vim
			PyCharm
			Jupyter Notebooks
	Appendix C: Getting Help
		First Steps
			Try It Again
			Take a Break
			Refer to This Book’s Resources
		Searching Online
			Stack Overflow
			The Official Python Documentation
			Official Library Documentation
			r/learnpython
			Blog Posts
		Discord
		Slack
	Appendix D: Using Git for Version Control
		Installing Git
			Configuring Git
		Making a Project
		Ignoring Files
		Initializing a Repository
		Checking the Status
		Adding Files to the Repository
		Making a Commit
		Checking the Log
		The Second Commit
		Abandoning Changes
		Checking Out Previous Commits
		Deleting the Repository
	Appendix E: Troubleshooting Deployments
		Understanding Deployments
		Basic Troubleshooting
			Follow Onscreen Suggestions
			Read the Log Output
		OS-Specific Troubleshooting
			Deploying from Windows
			Deploying from macOS
			Deploying from Linux
		Other Deployment Approaches
Index
Resources
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