Table Of ContentPython
E S S E N T I A L R E F E R E N C E
Fourth Edition
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From the Library of Lee Bogdanoff
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From the Library of Lee Bogdanoff
Python
E S S E N T I A L R E F E R E N C E
Fourth Edition
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From the Library of Lee Bogdanoff
❖
For Paula,Thomas.,and his brother on the way.
❖
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From the Library of Lee Bogdanoff
Contents at a Glance
Introduction 1
Part I: The Python Language
1 A Tutorial Introduction 5
2 Lexical Conventions and Syntax 25
3 Types and Objects 33
4 Operators and Expressions 65
5 Program Structure and Control Flow 81
6 Functions and Functional Programming 93
7 Classes and Object-Oriented Programming 117
8 Modules,Packages,and Distribution 143
9 Input and Output 157
10 Execution Environment 173
11 Testing,Debugging,Profiling,and Tuning 181
Part II: The Python Library ptg
12 Built-In Functions 201
13 Python Runtime Services 219
14 Mathematics 243
15 Data Structures,Algorithms,and Code Simplification 257
16 String and Text Handling 277
17 Python Database Access 297
18 File and Directory Handling 313
19 Operating System Services 331
20 Threads and Concurrency 413
21 Network Programming and Sockets 449
22 Internet Application Programming 497
23 Web Programming 531
24 Internet Data Handling and Encoding 545
25 Miscellaneous Library Modules 585
Part III: Extending and Embedding
26 Extending and Embedding Python 591
Appendix: Python 3 621
Index 639
From the Library of Lee Bogdanoff
Table of Contents
Introduction 1
I: The Python Language
1 A Tutorial Introduction 5
Running Python 5
Variables and Arithmetic Expressions 7
Conditionals 9
File Input and Output 10
Strings 11
Lists 12
Tuples 14
Sets 15
Dictionaries 16
Iteration and Looping 17
Functions 18
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Generators 19
Coroutines 20
Objects and Classes 21
Exceptions 22
Modules 23
Getting Help 24
2 Lexical Conventions and Syntax 25
Line Structure and Indentation 25
Identifiers and Reserved Words 26
Numeric Literals 26
String Literals 27
Containers 29
Operators,Delimiters,and Special Symbols 30
Documentation Strings 30
Decorators 30
Source Code Encoding 31
3 Types and Objects 33
Terminology 33
Object Identity and Type 33
Reference Counting and Garbage Collection 34
References and Copies 35
From the Library of Lee Bogdanoff
viii Contents
First-Class Objects 36
Built-in Types for Representing Data 37
The None Type 38
Numeric Types 38
Sequence Types 39
Mapping Types 44
Set Types 46
Built-in Types for Representing Program Structure 47
Callable Types 47
Classes,Types,and Instances 50
Modules 50
Built-in Types for Interpreter Internals 51
Code Objects 51
Frame Objects 52
Traceback Objects 52
Generator Objects 53
Slice Objects 53
Ellipsis Object 54
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Object Behavior and Special Methods 54
Object Creation and Destruction 54
Object String Representation 55
Object Comparison and Ordering 56
Type Checking 57
Attribute Access 57
Attribute Wrapping and Descriptors 58
Sequence and Mapping Methods 58
Iteration 59
Mathematical Operations 60
Callable Interface 62
Context Management Protocol 62
Object Inspection and dir() 63
4 Operators and Expressions 65
Operations on Numbers 65
Operations on Sequences 67
String Formatting 70
Advanced String Formatting 72
Operations on Dictionaries 74
Operations on Sets 75
Augmented Assignment 75
From the Library of Lee Bogdanoff
Contents ix
The Attribute (.) Operator 76
The Function Call () Operator 76
Conversion Functions 76
Boolean Expressions and Truth Values 77
Object Equality and Identity 78
Order of Evaluation 78
Conditional Expressions 79
5 Program Structure and Control Flow 81
Program Structure and Execution 81
Conditional Execution 81
Loops and Iteration 82
Exceptions 84
Built-in Exceptions 86
Defining New Exceptions 88
Context Managers and the with Statement 89
Assertions and __debug__ 91
6 Functions and Functional Programming 93
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Functions 93
Parameter Passing and Return Values 95
Scoping Rules 96
Functions as Objects and Closures 98
Decorators 101
Generators and yield 102
Coroutines and yield Expressions 104
Using Generators and Coroutines 106
List Comprehensions 108
Generator Expressions 109
Declarative Programming 110
The lambda Operator 112
Recursion 112
Documentation Strings 113
Function Attributes 114
eval(),exec(),and compile() 115
7 Classes and Object-Oriented Programming 117
TheclassStatement 117
Class Instances 118
Scoping Rules 118
Inheritance 119
From the Library of Lee Bogdanoff
