The Python Tutorial — Python 2.7

8/17/2019 The Python Tutorial — Python 2.7

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10/5/2016 The Python Tutorial — Python 2.7.11 documentation

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The Python Tutorial

Python is an easy to learn, powerful programming language. It has efficient high-level

data structures and a simple but effective approach to object-oriented programming.

Python’s elegant syntax and dynamic typing, together with its interpreted nature, make it

an ideal language for scripting and rapid application development in many areas on most

platforms.

The Python interpreter and the extensive standard library are freely available in source or

binary form for all major platforms from the Python Web site, https://www.python.org/, and

may be freely distributed. The same site also contains distributions of and pointers to

many free third party Python modules, programs and tools, and additional

documentation.

The Python interpreter is easily extended with new functions and data types implemented

in C or C++ (or other languages callable from C). Python is also suitable as an extension

language for customizable applications.

This tutorial introduces the reader informally to the basic concepts and features of the

Python language and system. It helps to have a Python interpreter handy for hands-on

experience, but all examples are self-contained, so the tutorial can be read off-line as

well.

For a description of standard objects and modules, see The Python Standard Library.

The Python Language Reference gives a more formal definition of the language. To write

extensions in C or C++, read Extending and Embedding the Python Interpreter andPython/C API Reference Manual. There are also several books covering Python in depth.

This tutorial does not attempt to be comprehensive and cover every single feature, or

even every commonly used feature. Instead, it introduces many of Python’s most

noteworthy features, and will give you a good idea of the language’s flavor and style.

After reading it, you will be able to read and write Python modules and programs, and

you will be ready to learn more about the various Python library modules described in

The Python Standard Library.

The Glossary is also worth going through.

1. Whetting Your Appetite

2. Using the Python Interpreter

2.1. Invoking the Interpreter

2.1.1. Argument Passing

2.1.2. Interactive Mode

2.2. The Interpreter and Its Environment

2.2.1. Source Code Encoding

3. An Informal Introduction to Python

3.1. Using Python as a Calculator

3.1.1. Numbers

3.1.2. Strings

3.1.3. Unicode Strings

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3.1.4. Lists

3.2. First Steps Towards Programming

4. More Control Flow Tools

4.1. if Statements

4.2. for Statements

4.3. The range() Function

4.4. break and continue Statements, and else Clauses on Loops

4.5. pass Statements4.6. Defining Functions

4.7. More on Defining Functions

4.7.1. Default Argument Values

4.7.2. Keyword Arguments

4.7.3. Arbitrary Argument Lists

4.7.4. Unpacking Argument Lists

4.7.5. Lambda Expressions

4.7.6. Documentation Strings

4.8. Intermezzo: Coding Style5. Data Structures

5.1. More on Lists

5.1.1. Using Lists as Stacks

5.1.2. Using Lists as Queues

5.1.3. Functional Programming Tools

5.1.4. List Comprehensions

5.1.4.1. Nested List Comprehensions

5.2. The del statement

5.3. Tuples and Sequences5.4. Sets

5.5. Dictionaries

5.6. Looping Techniques

5.7. More on Conditions

5.8. Comparing Sequences and Other Types

6. Modules

6.1. More on Modules

6.1.1. Executing modules as scripts

6.1.2. The Module Search Path

6.1.3. “Compiled” Python files

6.2. Standard Modules

6.3. The dir() Function

6.4. Packages

6.4.1. Importing * From a Package

6.4.2. Intra-package References

6.4.3. Packages in Multiple Directories

7. Input and Output

7.1. Fancier Output Formatting

7.1.1. Old string formatting7.2. Reading and Writing Files

7.2.1. Methods of File Objects

7.2.2. Saving structured data with json

https://docs.python.org/2/tutorial/inputoutput.html#saving-structured-data-with-jsonhttps://docs.python.org/2/tutorial/inputoutput.html#methods-of-file-objectshttps://docs.python.org/2/tutorial/inputoutput.html#reading-and-writing-fileshttps://docs.python.org/2/tutorial/inputoutput.html#old-string-formattinghttps://docs.python.org/2/tutorial/inputoutput.html#fancier-output-formattinghttps://docs.python.org/2/tutorial/inputoutput.htmlhttps://docs.python.org/2/tutorial/modules.html#packages-in-multiple-directorieshttps://docs.python.org/2/tutorial/modules.html#intra-package-referenceshttps://docs.python.org/2/tutorial/modules.html#importing-from-a-packagehttps://docs.python.org/2/tutorial/modules.html#packageshttps://docs.python.org/2/tutorial/modules.html#the-dir-functionhttps://docs.python.org/2/tutorial/modules.html#standard-moduleshttps://docs.python.org/2/tutorial/modules.html#compiled-python-fileshttps://docs.python.org/2/tutorial/modules.html#the-module-search-pathhttps://docs.python.org/2/tutorial/modules.html#executing-modules-as-scriptshttps://docs.python.org/2/tutorial/modules.html#more-on-moduleshttps://docs.python.org/2/tutorial/modules.htmlhttps://docs.python.org/2/tutorial/datastructures.html#comparing-sequences-and-other-typeshttps://docs.python.org/2/tutorial/datastructures.html#more-on-conditionshttps://docs.python.org/2/tutorial/datastructures.html#looping-techniqueshttps://docs.python.org/2/tutorial/datastructures.html#dictionarieshttps://docs.python.org/2/tutorial/datastructures.html#setshttps://docs.python.org/2/tutorial/datastructures.html#tuples-and-sequenceshttps://docs.python.org/2/tutorial/datastructures.html#the-del-statementhttps://docs.python.org/2/tutorial/datastructures.html#nested-list-comprehensionshttps://docs.python.org/2/tutorial/datastructures.html#list-comprehensionshttps://docs.python.org/2/tutorial/datastructures.html#functional-programming-toolshttps://docs.python.org/2/tutorial/datastructures.html#using-lists-as-queueshttps://docs.python.org/2/tutorial/datastructures.html#using-lists-as-stackshttps://docs.python.org/2/tutorial/datastructures.html#more-on-listshttps://docs.python.org/2/tutorial/datastructures.htmlhttps://docs.python.org/2/tutorial/controlflow.html#intermezzo-coding-stylehttps://docs.python.org/2/tutorial/controlflow.html#documentation-stringshttps://docs.python.org/2/tutorial/controlflow.html#lambda-expressionshttps://docs.python.org/2/tutorial/controlflow.html#unpacking-argument-listshttps://docs.python.org/2/tutorial/controlflow.html#arbitrary-argument-listshttps://docs.python.org/2/tutorial/controlflow.html#keyword-argumentshttps://docs.python.org/2/tutorial/controlflow.html#default-argument-valueshttps://docs.python.org/2/tutorial/controlflow.html#more-on-defining-functionshttps://docs.python.org/2/tutorial/controlflow.html#defining-functionshttps://docs.python.org/2/tutorial/controlflow.html#pass-statementshttps://docs.python.org/2/tutorial/controlflow.html#break-and-continue-statements-and-else-clauses-on-loopshttps://docs.python.org/2/tutorial/controlflow.html#the-range-functionhttps://docs.python.org/2/tutorial/controlflow.html#for-statementshttps://docs.python.org/2/tutorial/controlflow.html#if-statementshttps://docs.python.org/2/tutorial/controlflow.htmlhttps://docs.python.org/2/tutorial/introduction.html#first-steps-towards-programminghttps://docs.python.org/2/tutorial/introduction.html#lists


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8. Errors and Exceptions

8.1. Syntax Errors

8.2. Exceptions

8.3. Handling Exceptions

8.4. Raising Exceptions

8.5. User-defined Exceptions

8.6. Defining Clean-up Actions

8.7. Predefined Clean-up Actions9. Classes

9.1. A Word About Names and Objects

9.2. Python Scopes and Namespaces

9.3. A First Look at Classes

9.3.1. Class Definition Syntax

9.3.2. Class Objects

9.3.3. Instance Objects

9.3.4. Method Objects

9.3.5. Class and Instance Variables9.4. Random Remarks

9.5. Inheritance

9.5.1. Multiple Inheritance

9.6. Private Variables and Class-local References

9.7. Odds and Ends

9.8. Exceptions Are Classes Too

9.9. Iterators

9.10. Generators

9.11. Generator Expressions

10. Brief Tour of the Standard Library

10.1. Operating System Interface

10.2. File Wildcards

10.3. Command Line Arguments

10.4. Error Output Redirection and Program Termination

10.5. String Pattern Matching

10.6. Mathematics

10.7. Internet Access

10.8. Dates and Times

10.9. Data Compression10.10. Performance Measurement

10.11. Quality Control

10.12. Batteries Included

11. Brief Tour of the Standard Library – Part II

11.1. Output Formatting

11.2. Templating

11.3. Working with Binary Data Record Layouts

11.4. Multi-threading

11.5. Logging11.6. Weak References

11.7. Tools for Working with Lists

11.8. Decimal Floating Point Arithmetic

12. What Now?

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13. Interactive Input Editing and History Substitution

13.1. Line Editing

13.2. History Substitution

13.3. Key Bindings

13.4. Alternatives to the Interactive Interpreter

14. Floating Point Arithmetic: Issues and Limitations

14.1. Representation Error

15. Appendix15.1. Interactive Mode

15.1.1. Error Handling

15.1.2. Executable Python Scripts

15.1.3. The Interactive Startup File

15.1.4. The Customization Modules
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The Python Tutorial — Python 2.7

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