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A Python Book

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A Python Book A Python Book A Python Book: Beginning Python, Advanced Python, and Python Exercises Author: Dave Kuhlman Contact: [email protected] Address: http://www.davekuhlman.org Page 1 A Python Book Revision 1.3a Date December 15, 2013 Copyright Copyright (c) 2009 Dave Kuhlman. All Rights Reserved. This document is subject to the provisions of the Open Source MIT License http://www.opensource.org/licenses/mit-license.php. Abstract This document is a self-learning document for a course in Python programming. This course contains (1) a part for beginners, (2) a discussion of several advanced topics that are of interest to Python programmers, and (3) a Python workbook with lots of exercises. Page 2 A Python Book Contents 1 Part 1 -- Beginning Python...........................................................................................10 1.1 Introductions Etc...................................................................................................10 1.1.1 Resources.......................................................................................................11 1.1.2 A general description of Python....................................................................12 1.1.3 Interactive Python..........................................................................................15 1.2 Lexical matters......................................................................................................15 1.2.1 Lines..............................................................................................................15 1.2.2 Comments......................................................................................................16 1.2.3 Names and tokens..........................................................................................16 1.2.4 Blocks and indentation..................................................................................16 1.2.5 Doc strings.....................................................................................................17 1.2.6 Program structure..........................................................................................17 1.2.7 Operators.......................................................................................................18 1.2.8 Also see.........................................................................................................19 1.2.9 Code evaluation.............................................................................................19 1.3 Statements and inspection -- preliminaries...........................................................20 1.4 Built-in data-types.................................................................................................21 1.4.1 Numeric types................................................................................................21 1.4.2 Tuples and lists..............................................................................................21 1.4.3 Strings............................................................................................................24 1.4.3.1 The new string.format method...............................................................26 1.4.3.2 Unicode strings......................................................................................27 1.4.4 Dictionaries....................................................................................................29 1.4.5 Files...............................................................................................................32 1.4.6 Other built-in types........................................................................................35 1.4.6.1 The None value/type..............................................................................35 1.4.6.2 Boolean values.......................................................................................36 1.4.6.3 Sets and frozensets.................................................................................36 1.5 Functions and Classes -- A Preview......................................................................36 1.6 Statements.............................................................................................................37 1.6.1 Assignment statement....................................................................................37 1.6.2 import statement............................................................................................39 1.6.3 print statement...............................................................................................41 1.6.4 if: elif: else: statement...................................................................................43 1.6.5 for: statement.................................................................................................44 1.6.6 while: statement.............................................................................................48 Page 3 A Python Book 1.6.7 continue and break statements.......................................................................48 1.6.8 try: except: statement.....................................................................................49 1.6.9 raise statement...............................................................................................51 1.6.10 with: statement.............................................................................................52 1.6.10.1 Writing a context manager...................................................................52 1.6.10.2 Using the with: statement....................................................................53 1.6.11 del................................................................................................................54 1.6.12 case statement..............................................................................................55 1.7 Functions, Modules, Packages, and Debugging....................................................55 1.7.1 Functions.......................................................................................................55 1.7.1.1 The def statement...................................................................................55 1.7.1.2 Returning values....................................................................................55 1.7.1.3 Parameters..............................................................................................56 1.7.1.4 Arguments..............................................................................................56 1.7.1.5 Local variables.......................................................................................57 1.7.1.6 Other things to know about functions....................................................57 1.7.1.7 Global variables and the global statement.............................................58 1.7.1.8 Doc strings for functions.......................................................................60 1.7.1.9 Decorators for functions........................................................................60 1.7.2 lambda...........................................................................................................61 1.7.3 Iterators and generators.................................................................................62 1.7.4 Modules.........................................................................................................67 1.7.4.1 Doc strings for modules.........................................................................68 1.7.5 Packages........................................................................................................68 1.8 Classes...................................................................................................................69 1.8.1 A simple class................................................................................................69 1.8.2 Defining methods..........................................................................................70 1.8.3 The constructor..............................................................................................70 1.8.4 Member variables..........................................................................................70 1.8.5 Calling methods.............................................................................................71 1.8.6 Adding inheritance........................................................................................71 1.8.7 Class variables...............................................................................................72 1.8.8 Class methods and static methods.................................................................72 1.8.9 Properties.......................................................................................................74 1.8.10 Interfaces.....................................................................................................75 1.8.11 New-style classes.........................................................................................75 1.8.12 Doc strings for classes.................................................................................77 1.8.13 Private members..........................................................................................77 1.9 Special Tasks.........................................................................................................77 1.9.1 Debugging tools.............................................................................................77 Page 4 A Python Book 1.9.2 File input and output......................................................................................78
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