The Hitchhiker’s Guide to Python: Best Practices for Development

322 Pages·2016·5.238 MB·English

by  Kenneth Reitz, Tanya Schlusser

The
H itchhiker’s
G uide to
P ython
BEST PRACTICES FOR DEVELOPMENT
Kenneth Reitz & Tanya Schlusser

The Hitchhiker’s Guide to Python
Best Practices for Development
Kenneth Reitz and Tanya Schlusser
BBeeiijjiinngg BBoossttoonn FFaarrnnhhaamm SSeebbaassttooppooll TTookkyyoo
The Hitchhiker’s Guide to Python
by Kenneth Reitz and Tanya Schlusser
Copyright © 2016 Kenneth Reitz, Tanya Schlusser. All rights reserved.
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[LSI]
Dedicated to you

Table of Contents
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
Part I. Getting Started
1. Picking an Interpreter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
The State of Python 2 Versus Python 3 3
Recommendations 4
So…3? 4
Implementations 5
CPython 5
Stackless 5
PyPy 6
Jython 6
IronPython 6
PythonNet 6
Skulpt 7
MicroPython 7
2. Properly Installing Python. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Installing Python on Mac OS X 9
Setuptools and pip 11
virtualenv 11
Installing Python on Linux 12
Setuptools and pip 12
Development Tools 13
virtualenv 14
Installing Python on Windows 15
v
Setuptools and pip 17
virtualenv 18
Commercial Python Redistributions 18
3. Your Development Environment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Text Editors 22
Sublime Text 23
Vim 23
Emacs 25
TextMate 26
Atom 26
Code 27
IDEs 27
PyCharm/IntelliJ IDEA 29
Aptana Studio 3/Eclipse + LiClipse + PyDev 29
WingIDE 30
Spyder 30
NINJA-IDE 30
Komodo IDE 31
Eric (the Eric Python IDE) 31
Visual Studio 32
Enhanced Interactive Tools 32
IDLE 32
IPython 33
bpython 33
Isolation Tools 33
Virtual Environments 34
pyenv 36
Autoenv 36
virtualenvwrapper 37
Buildout 38
Conda 38
Docker 39
Part II. Getting Down to Business
4. Writing Great Code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Code Style 43
PEP 8 44
PEP 20 (a.k.a. The Zen of Python) 45
General Advice 46
vi | Table of Contents
Conventions 52
Idioms 54
Common Gotchas 58
Structuring Your Project 61
Modules 61
Packages 65
Object-Oriented Programming 66
Decorators 67
Dynamic Typing 68
Mutable and Immutable Types 69
Vendorizing Dependencies 71
Testing Your Code 72
Testing Basics 74
Examples 76
Other Popular Tools 80
Documentation 82
Project Documentation 82
Project Publication 83
Docstring Versus Block Comments 84
Logging 84
Logging in a Library 85
Logging in an Application 86
Choosing a License 88
Upstream Licenses 88
Options 88
Licensing Resources 90
5. Reading Great Code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Common Features 92
HowDoI 93
Reading a Single-File Script 93
Structure Examples from HowDoI 96
Style Examples from HowDoI 97
Diamond 99
Reading a Larger Application 100
Structure Examples from Diamond 105
Style Examples from Diamond 109
Tablib 112
Reading a Small Library 112
Structure Examples from Tablib 116
Style Examples from Tablib 124
Requests 126
Table of Contents | vii
Reading a Larger Library 126
Structure Examples from Requests 130
Style Examples from Requests 135
Werkzeug 140
Reading Code in a Toolkit 141
Style Examples from Werkzeug 148
Structure Examples from Werkzeug 149
Flask 155
Reading Code in a Framework 156
Style Examples from Flask 162
Structure Examples from Flask 163
6. Shipping Great Code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Useful Vocabulary and Concepts 168
Packaging Your Code 169
Conda 169
PyPI 170
Freezing Your Code 172
PyInstaller 174
cx_Freeze 176
py2app 177
py2exe 178
bbFreeze 178
Packaging for Linux-Built Distributions 179
Executable ZIP Files 180
Part III. Scenario Guide
7. User Interaction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
Jupyter Notebooks 185
Command-Line Applications 186
GUI Applications 194
Widget Libraries 194
Game Development 200
Web Applications 200
Web Frameworks/Microframeworks 201
Web Template Engines 204
Web Deployment 209
8. Code Management and Improvement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Continuous Integration 213
viii | Table of Contents