Introducing Python: Modern Computing in Simple Packages. 3 Ed

Cover....1 Copyright....6 Table of Contents....9 Preface....27 Audience....28 Changes in the Third Edition....28 Outline....28 Python Versions....32 About the Author....32 Conventions Used in This Book....33 Using Code Examples....34 O’Reilly Online Learning....34 How to Contact Us....35 Acknowledgments....35 Part I. Stronghold....37 Chapter 1. Introduction....39 Mysteries....39 Little Python Programs....42 Setup....44 Install Python....45 Upgrade Python....45 Run Python Programs....45 The Python Interactive Interpreter....46 Python Files....46 Built-In Python Features....47 The Python Standard Library....47 Third-Party Python Packages....47 A Bigger Example....47 Review/Preview....50 Chapter 2. Types and Variables....51 A Computer....51 Bits and Bytes....52 Multibyte Types....55 Variables....57 Assign a Value to a Variable....57 Change the Value of a Variable....60 Delete a Variable....61 Name Variables....62 Follow Naming Conventions....63 Python Types....63 Specify Values....64 Objects as Plastic Boxes in Memory....65 Review/Preview....65 Practice....65 Chapter 3. Numbers....67 Booleans....67 Integers....68 Literal Integers....69 Integer Operations....70 Integers and Variables....72 Precedence....74 Bases....75 Type Conversions....77 How Big Is an int?....79 Floats....80 Floats Are Not Exact....82 Fractions....82 Decimals....83 Math Functions....83 Review/Preview....83 Practice....83 Chapter 4. Strings....85 Create with Quotes....86 Create with str()....88 Escape with \....89 Combine with +....90 Duplicate with *....91 Get a Character by [ offset ]....91 Get a Substring with a Slice....92 Get Length with len()....94 Split with split()....95 Combine with join()....95 Substitute with replace()....95 Work with Prefixes and Suffixes....96 Strip with strip()....97 Search and Select....98 Change Case....99 Set Alignment....100 Apply Formatting....100 Old style: %....101 New style: {} and format()....104 Newest Style: f-strings....105 Review/Preview....106 Practice....107 Chapter 5. Bytes and Bytearray....109 Bytes....109 Create with Quotes....110 Create with bytes()....110 Create from a Hex String....111 Decode and Encode Bytes and Strings....112 Convert to a Hex String....112 Get One Byte by [ offset ]....112 Get a Slice....112 Combine with +....113 Repeat with *....113 Bytearray....113 Create with bytearray()....113 Get One Byte by [ offset ]....114 Get Multiple Bytes with a Slice....114 Modify One Byte by [ offset ]....114 Modify Multiple Bytes with replace()....114 Modify Multiple Bytes with a Slice....115 Insert a Byte with insert()....115 Append One Byte with append()....115 Append Multiple Bytes with extend()....115 Combine with +....116 Repeat with *....116 Review/Preview....116 Practice....116 Chapter 6. If and Match....117 Comment with #....117 Continue Lines with \....118 Compare with if, elif, and else....119 What Is True?....122 Do Multiple Comparisons with in....123 New: I Am the Walrus....124 Match....125 Simple Matches....126 Structural Matches....127 Review/Preview....127 Practice....128 Chapter 7. For and While....129 Repeat with while....129 Cancel with break....130 Skip Ahead with continue....130 Check break Use with else....131 Iterate with for and in....131 Cancel with break....132 Skip with continue....132 Check break Use with else....132 Generate Number Sequences with range()....133 Review/Preview....134 Practice....134 Chapter 8. Tuples and Lists....135 Tuples....136 Create with Commas and ()....136 Create with tuple()....138 Get an Item by [ offset ]....138 Combine with +....138 Duplicate with *....138 Compare....138 Iterate with for and in....139 Modify?....139 Lists....140 Create with []....140 Create or Convert with list()....140 Create from a String with split()....141 Get an Item by [ offset ]....141 Get Items with a Slice....142 Add an Item to the End with append()....143 Add an Item by Offset with insert()....143 Duplicate with *....144 Combine with extend() or +....144 Change an Item with [ offset ]....144 Change Items with a Slice....145 Delete an Item by Offset with del....145 Delete an Item by Value with remove()....146 Get an Item by Offset and Delete It with pop()....146 Delete All Items with clear()....147 Find an Item’s Offset by Value with index()....147 Test for a Value with in....147 Count Occurrences of a Value with count()....148 Convert a List to a String with join()....148 Reorder Items with sort() or sorted()....149 Get Length with len()....149 Assign with =....150 Copy with copy(), list(), or a Slice....150 Copy Everything with deepcopy()....151 Compare Lists....152 Iterate with for and in....152 Iterate Multiple Sequences with zip()....153 Iterate Multiple Sequences with zip_longest()....154 Create a List with a Comprehension....155 Create Lists of Lists....157 Tuples Versus Lists....158 There Are No Tuple Comprehensions....158 Review/Preview....159 Practice....159 Chapter 9. Dictionaries and Sets....161 Dictionaries....161 Create with {}....162 Create with dict()....162 Convert with dict()....163 Add or Change an Item by [ key ]....164 Get an Item by [ key ] or with get()....165 Iterate with for and in....166 Get Length with len()....167 Combine/update dicts....167 Delete an Item by Key with del....169 Get an Item by Key and Delete It with pop( key )....169 Delete All Items with clear()....170 Test for a Key with in....170 Assign with =....170 Copy with copy()....171 Copy Everything with deepcopy()....171 Compare Dictionaries....172 Use Dictionary Comprehensions....173 Sets....174 Create with set() or {}....174 Get Length with len()....175 Add an Item with add()....176 Delete an Item with remove()....176 Combine with |....176 Iterate with for and in....176 Test for a Value with in....177 Use Combinations and Operators....177 Create Set Comprehensions....181 Create an Immutable Set with frozenset()....181 Review/Preview....182 Practice....182 Chapter 10. Functions....185 Define a Function with def....185 Call a Function with Parentheses....186 Arguments and Parameters....187 None, Truthiness, and Falsiness....188 Positional Arguments....190 Keyword Arguments....191 Default Parameter Values....191 Pack/Unpack Positional Arguments with *....192 Pack/Unpack Keyword Arguments with **....194 Keyword-Only (*) and Position-Only (/) Arguments....195 Mutable and Immutable Arguments....197 Docstrings....198 Functions Are First-Class Citizens....198 Function Arguments Are Not a Tuple....201 Inner Functions....201 Closures....202 Anonymous Functions: Lambda....203 Generators....204 Generator Functions....204 Generator Comprehensions....206 Decorators....206 Namespaces and Scope....209 Dunder Names....211 Recursion....211 Async Functions, Briefly....213 Exceptions....213 Handle Errors with try and except....214 Use Finally....215 Make Your Own Exceptions....216 Review/Preview....216 Practice....217 Chapter 11. Objects....219 What Are Objects?....219 Simple Objects....220 Define a Class with class....220 Assign Attributes....221 Methods....222 Initialization....222 Inheritance....224 Inherit from a Parent Class....224 Override a Method....225 Add a Method....227 Get Help from Your Parent with super()....227 Use Multiple Inheritance....228 Include Mixins....230 In self Defense....231 Attribute Access....231 Direct Access....231 Getters and Setters....232 Properties for Attribute Access....233 Properties for Computed Values....234 Name Mangling for Privacy....235 Class and Object Attributes....236 Method Types....237 Instance Methods....237 Class Methods....237 Static Methods....238 Duck Typing....238 Magic Methods....241 Aggregation and Composition....244 When to Use Objects or Something Else....244 Named Tuples....245 Dataclasses....247 Attrs....248 Review/Preview....248 Practice....249 Chapter 12. Modules and Packages....251 Modules and the import Statement....251 Import a Module....252 Import a Module with Another Name....254 Import Only What You Want from a Module....254 Packages....254 The Module Search Path....256 Relative and Absolute Imports....257 Namespace Packages....257 Modules Versus Objects....258 Goodies in the Python Standard Library....259 Handle Missing Keys with setdefault() and defaultdict()....259 Count Items with Counter()....261 Order by Key with OrderedDict()....263 Stack + Queue == deque....263 Iterate over Code Structures with itertools....264 Get Random....266 More Batteries: Get Other Python Code....267 Review/Preview....267 Practice....267 Part II. Tools....269 Chapter 13. Development Environment....271 Find Python Code....271 Install Packages....272 Use Pip....272 Install with a Native Package Manager....273 Install from Source....274 Virtual Environments....274 Virtualenv and Venv....275 Pipenv....276 Poetry....276 Conda....276 uv....276 Integrated Development Environments....277 IPython....278 Jupyter Notebook....280 JupyterLab....280 Source Control....280 Mercurial....281 Git....281 Review/Preview....284 Practice....284 Chapter 14. Type Hints and Documentation....285 Type Hints....285 Variable Hints....286 Function Hints....287 Mypy....287 Documentation....288 Comments....289 Docstrings....289 Markup Text Files....289 Review/Preview....289 Practice....290 Chapter 15. Testing....291 Pylint....291 Ruff....293 Unittest....294 Doctest....298 Pytest....299 Examples....300 Fixtures....301 Parametrization....303 Hypothesis....304 Nox....305 Continuous Integration....305 Review/Preview....306 Practice....306 Chapter 16. Debugging....307 Assert....308 Print....309 F-strings....309 Pprint()....310 IceCream....310 Decorators....311 Logging....312 Pdb....315 Breakpoint()....320 Review/Preview....321 Practice....321 Part III. Quests....323 Chapter 17. Text Data....325 Text Strings: Unicode....325 Python Unicode Strings....326 UTF-8....329 Encode....330 Decode....331 HTML Entities....333 Normalization....334 Text Strings: Regular Expressions....335 Find Exact Beginning Match with match()....336 Find First Match with search()....338 Find All Matches with findall()....338 Split at Matches with split()....338 Replace at Matches with sub()....339 Patterns....339 Using Special Characters....339 Using Specifiers....341 Specifying match() Output....343 Review/Preview....344 Practice....344 Chapter 18. Binary Data....345 Convert Binary Data with struct....345 Extraction with Binary Data Tools....348 Convert Bytes/Strings with binascii()....349 Use Bit Operators....349 Review/Preview....350 Practice....350 Chapter 19. Dates and Times....351 Leap Year....352 The datetime Module....353 The time Module....355 Read and Write Dates and Times....357 All the Conversions....361 Alternative Modules....362 Review/Preview....362 Practice....363 Chapter 20. Files....365 File Input and Output....365 Create or Open with open()....366 Write a Text File with print()....367 Write a Text File with write()....367 Read a Text File with read(), readline(), or readlines()....369 Write a Binary File with write()....370 Read a Binary File with read()....371 Close Files Automatically by Using with....371 Change Position with seek()....371 Memory Mapping....373 File Operations....374 Check Existence with exists()....374 Check Type with isfile()....374 Copy with copy()....375 Change Name with rename()....375 Link with link() or symlink()....375 Change Permissions with chmod()....376 Change Ownership with chown()....376 Delete a File with remove()....376 Directory Operations....376 Create with mkdir()....377 Delete with rmdir()....377 List Contents with listdir()....377 Change Current Directory with chdir()....378 List Matching Files with glob()....378 Pathnames....379 Get a Pathname with abspath()....379 Get a symlink Pathname with realpath()....380 Build a Pathname with os.path.join()....380 Use pathlib....380 BytesIO and StringIO....381 File Formats: Determination....383 Review/Preview....383 Practice....383 Chapter 21. Data in Time: Concurrency....385 Programs and Processes....385 Create a Process with subprocess....386 Create a Process with multiprocessing....387 Kill a Process with terminate()....388 Get System Info with os....389 Get Process Info with psutil....389 Command Automation....390 Invoke....390 Other Command Helpers....391 Concurrency....392 Queues....393 Processes....393 Threads....395 The GIL....397 Concurrent.futures....398 Green Threads and gevent....401 Twisted....403 asyncio....405 Coroutines and Event Loops....406 Asyncio Alternatives....408 Async Versus…​....409 Async Frameworks and Servers....410 Redis....411 Beyond Queues....414 Review/Preview....415 Practice....415 Chapter 22. Data in Space: Networks....417 TCP/IP....417 Sockets....418 Scapy....423 Netcat....423 Networking Patterns....424 The Request-Reply Pattern....424 Request-Reply: ZeroMQ....425 Request-Reply: Other Messaging Tools....429 The Publish-Subscribe Pattern....429 Pub-Sub: Redis....429 Pub-Sub: ZeroMQ....431 Pub-Sub: Other Tools....433 Internet Services....433 Domain Name System....433 Python Email Modules....434 Other Protocols....434 Web Services and APIs....435 Data Serialization....435 Serialize with pickle....436 Use Other Serialization Formats....437 Remote Procedure Calls....438 XML-RPC....438 JSON RPC....439 MessagePack RPC....440 zerorpc....441 gRPC....442 Remote Management....443 Big Fat Data....443 Hadoop....443 Spark....444 Disco....444 Dask....444 Clouds....444 Amazon Web Services....446 Google Cloud....446 Microsoft Azure....446 OpenStack....446 Docker....446 Kubernetes....447 Review/Preview....447 Practice....447 Chapter 23. Data in a Box: Persistent Storage....449 Text Files....449 Tabular and Delimited Text Files....450 CSV....450 XML....452 An XML Security Note....454 HTML....455 JSON....455 YAML....458 TOML....460 Tablib....460 Configuration Files....460 Binary Files....461 Padded Binary Files and Memory Mapping....461 Spreadsheets....461 HDF5....462 TileDB....462 Relational Databases....462 SQL....463 DB-API....465 SQLite....465 DuckDB....467 MySQL....467 PostgreSQL....468 SQLAlchemy....468 Other Database Access Packages....474 NoSQL Data Stores....475 The dbm Family....475 Memcached....476 Redis....477 Redis Alternative: Valkey?....484 Document Databases....484 Time-Series Databases....485 Graph Databases....485 Other NoSQL....486 Full-Text Databases....486 Vector Databases....486 Geospatial Databases....487 Review/Preview....487 Practice....487 Chapter 24. The Web....489 Web Basics....490 HTTP Testing....491 Telnet....491 curl....492 HTTPie....493 httpbin....494 Web Clients....494 The Standard Library....494 Requests....496 Other Web Clients....498 Web Servers....500 The Simplest Python Web Server....500 Web Server Gateway Interface....502 ASGI....502 Apache....503 NGINX....504 Other Python Web Servers....504 Web Server Frameworks....505 Bottle....506 Flask....508 Django....512 FastAPI....513 Litestar....513 Database Frameworks....514 Web Services and Automation....515 webbrowser....515 webview....515 Web APIs and REST....516 WebSockets....517 Webhooks....518 Web Frontends....518 htmx....519 FastHTML....519 Crawl and Scrape....520 Scrapy....520 Beautiful Soup....521 Requests-HTML....522 Let’s Watch a Movie....522 Review/Preview....525 Practice....525 Chapter 25. Data Science....527 Standard Python....528 Format Conversions....529 Math....529 Complex Numbers....531 Calculate Accurate Floating Point Values with decimal....532 Perform Rational Arithmetic with fractions....533 Use Packed Sequences with array....533 Statistics....533 Matrix Multiplication....534 NumPy....534 Make an Array with array()....534 Make an Array with arange()....535 Make an Array with zeros(), ones(), or random()....536 Change an Array’s Shape with reshape()....537 Get an Element with []....538 Array Math....539 Linear Algebra....539 SciPy....540 pandas....541 Polars....543 DuckDB....543 Data Visualization....544 Review/Preview....545 Practice....545 Chapter 26. AI....547 It Turns Out…​....548 Expert Systems....548 Perceptrons....548 The Breakthrough....549 Image Recognition: ImageNet and AlexNet....549 Large Language Models....549 The ChatGPT Moment....550 Retrieval Augmented Generation....550 Agents....550 Efficiency....551 Create Models: Python Frameworks....551 Current Models....552 A Million Models: Hugging Face....552 Working Examples With Ollama....553 Install Ollama....553 Choose a Model....554 Choose Another Model....555 Ollama References....557 References....558 Review/Preview....558 Practice....559 Chapter 27. Performance....561 Computer Hardware....561 Measure Timing....563 Profile....567 Algorithms and Data Structures....568 Arrays Versus Lists and Tuples....569 Cache....569 Cython....570 NumPy and SciPy....570 C or Rust Extensions....570 Taichi....571 PyPy....571 Numba....571 Standard Python JIT....572 Mojo....572 Background....573 Design....574 Examples....574 Limitations....575 Conclusion....575 Review/Preview....575 Practice....576 Appendix. Practice Answers....577 2. Types and Variables....577 3. Numbers....578 4. Strings....579 5. Bytes and Bytearray....583 6. If and Match....584 7. For and While....585 8. Tuples and Lists....587 9. Dictionaries and Sets....591 10. Functions....595 11. Objects....597 12. Modules and Packages....601 13. Development Environment....603 14. Type Hints and Documentation....604 15. Testing....604 16. Debugging....607 17. Text Data....607 18. Binary Data....611 19. Dates and Times....612 20. Files....613 21. Data in Time: Concurrency....615 22. Data in Space: Networks....615 23. Data in a Box: Persistent Storage....621 24. The Web....625 25. Data Science....627 26. AI....628 27. Performance....634 Index....637 About the Author....659 Colophon....660