book

Python Distilled

by David M. Beazley

September 2021

Beginner to intermediate

352 pages

11h 27m

English

Addison-Wesley Professional

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1.1 Running Python1.2 Python Programs1.3 Primitives, Variables, and Expressions1.4 Arithmetic Operators1.5 Conditionals and Control Flow1.6 Text Strings1.7 File Input and Output1.8 Lists1.9 Tuples1.10 Sets1.11 Dictionaries1.12 Iteration and Looping1.13 Functions1.14 Exceptions1.15 Program Termination1.16 Objects and Classes1.17 Modules1.18 Script Writing1.19 Packages1.20 Structuring an Application1.21 Managing Third-Party Packages1.22 Python: It Fits Your Brain
2.1 Literals2.2 Expressions and Locations2.3 Standard Operators2.4 In-Place Assignment2.5 Object Comparison2.6 Ordered Comparison Operators2.7 Boolean Expressions and Truth Values2.8 Conditional Expressions2.9 Operations Involving Iterables2.10 Operations on Sequences2.11 Operations on Mutable Sequences2.12 Operations on Sets2.13 Operations on Mappings2.14 List, Set, and Dictionary Comprehensions2.15 Generator Expressions2.16 The Attribute (.) Operator2.17 The Function Call () Operator2.18 Order of Evaluation2.19 Final Words: The Secret Life of Data
3.1 Program Structure and Execution3.2 Conditional Execution3.3 Loops and Iteration3.4 Exceptions3.5 Context Managers and the with Statement3.6 Assertions and __debug__3.7 Final Words

4.1 Essential Concepts4.2 Object Identity and Type4.3 Reference Counting and Garbage Collection4.4 References and Copies4.5 Object Representation and Printing4.6 First-Class Objects4.7 Using None for Optional or Missing Data4.8 Object Protocols and Data Abstraction4.9 Object Protocol4.10 Number Protocol4.11 Comparison Protocol4.12 Conversion Protocols4.13 Container Protocol4.14 Iteration Protocol4.15 Attribute Protocol4.16 Function Protocol4.17 Context Manager Protocol4.18 Final Words: On Being Pythonic
5.1 Function Definitions5.2 Default Arguments5.3 Variadic Arguments5.4 Keyword Arguments5.5 Variadic Keyword Arguments5.6 Functions Accepting All Inputs5.7 Positional-Only Arguments5.8 Names, Documentation Strings, and Type Hints5.9 Function Application and Parameter Passing5.10 Return Values5.11 Error Handling5.12 Scoping Rules5.13 Recursion5.14 The lambda Expression5.15 Higher-Order Functions5.16 Argument Passing in Callback Functions5.17 Returning Results from Callbacks5.18 Decorators5.19 Map, Filter, and Reduce5.20 Function Introspection, Attributes, and Signatures5.21 Environment Inspection5.22 Dynamic Code Execution and Creation5.23 Asynchronous Functions and await5.24 Final Words: Thoughts on Functions and Composition
6.1 Generators and yield6.2 Restartable Generators6.3 Generator Delegation6.4 Using Generators in Practice6.5 Enhanced Generators and yield Expressions6.6 Applications of Enhanced Generators6.7 Generators and the Bridge to Awaiting6.8 Final Words: A Brief History of Generators and Looking Forward
7.1 Objects7.2 The class Statement7.3 Instances7.4 Attribute Access7.5 Scoping Rules7.6 Operator Overloading and Protocols7.7 Inheritance7.8 Avoiding Inheritance via Composition7.9 Avoiding Inheritance via Functions7.10 Dynamic Binding and Duck Typing7.11 The Danger of Inheriting from Built-in Types7.12 Class Variables and Methods7.13 Static Methods7.14 A Word about Design Patterns7.15 Data Encapsulation and Private Attributes7.16 Type Hinting7.17 Properties7.18 Types, Interfaces, and Abstract Base Classes7.19 Multiple Inheritance, Interfaces, and Mixins7.20 Type-Based Dispatch7.21 Class Decorators7.22 Supervised Inheritance7.23 The Object Life Cycle and Memory Management7.24 Weak References7.25 Internal Object Representation and Attribute Binding7.26 Proxies, Wrappers, and Delegation7.27 Reducing Memory Use with __slots__7.28 Descriptors7.29 Class Definition Process7.30 Dynamic Class Creation7.31 Metaclasses7.32 Built-in Objects for Instances and Classes7.33 Final Words: Keep It Simple
8.1 Modules and the import Statement8.2 Module Caching8.3 Importing Selected Names from a Module8.4 Circular Imports8.5 Module Reloading and Unloading8.6 Module Compilation8.7 The Module Search Path8.8 Execution as the Main Program8.9 Packages8.10 Imports Within a Package8.11 Running a Package Submodule as a Script8.12 Controlling the Package Namespace8.13 Controlling Package Exports8.14 Package Data8.15 Module Objects8.16 Deploying Python Packages8.17 The Penultimate Word: Start with a Package8.18 The Final Word: Keep It Simple
9.1 Data Representation9.2 Text Encoding and Decoding9.3 Text and Byte Formatting9.4 Reading Command-Line Options9.5 Environment Variables9.6 Files and File Objects9.7 I/O Abstraction Layers9.8 Standard Input, Output, and Error9.9 Directories9.10 The print() function9.11 Generating Output9.12 Consuming Input9.13 Object Serialization9.14 Blocking Operations and Concurrency9.15 Standard Library Modules9.15.25 threading Module9.16 Final Words
10.1 Built-in Functions10.2 Built-in Exceptions10.3 Standard Library10.4 Final Words: Use the Built-Ins

Content preview from Python Distilled

9. Input and Output

Input and output (I/O) is part of all programs. This chapter describes the essentials of Python I/O including data encoding, command-line options, environment variables, file I/O, and data serialization. Particular attention is given to programming techniques and abstractions that encourage proper I/O handling. The end of this chapter gives an overview of common standard library modules related to I/O.

9.1 Data Representation

The main problem of I/O is the outside world. To communicate with it, data must be properly represented, so that it can be manipulated. At the lowest level, Python works with two fundamental datatypes: bytes that represent raw uninterpreted data of any kind and text that represents Unicode characters. ...