Read and write bzip2-compressed files

https://github.com/nvawda/bz2file

Python 2 bindings for Cairo

https://github.com/pygobject/pycairo

Python client library for Apache Cassandra

https://github.com/datastax/python-driver

Let's Encrypt client

https://certbot.eff.org/ https://github.com/certbot/certbot https://github.com/certbot/certbot/tree/master/certbot

Mozilla SSL certificates

https://github.com/certifi/python-certifi

Foreign Function Interface for Python calling C code

https://cffi.readthedocs.io/en/latest/

Python attributes without boilerplate

https://github.com/hynek/characteristic

Universal encoding detector for Python

https://github.com/chardet/chardet/

Cross-platform API to print colored terminal text from Python applications

https://github.com/tartley/colorama

Drop-in replacement for argparse

https://github.com/bw2/ConfigArgParse

Simple but powerful config file reader and writer

https://github.com/DiffSK/configobj/

INI style configuration file parser

https://pypi.org/project/configparser/

Provides symbolic constant support to Python projects

https://pypi.org/project/constantly/

Code coverage measurement for Python

https://coverage.readthedocs.io/

Cryptographic recipes and primitives for Python developers

https://github.com/pyca/cryptography

Generate a version number from darcs history

https://pypi.org/project/darcsver/

Extensions to the standard Python datetime module

https://dateutil.readthedocs.io

Python bindings for the D-BUS messaging system

https://dbus.freedesktop.org/doc/dbus-python/

Better living through Python with decorators

https://github.com/micheles/decorator

DNS (Domain Name Service) library for Python

http://pydns.sourceforge.net/

DNS toolkit for Python

https://www.dnspython.org/

Python Documentation Utilities

https://docutils.sourceforge.io/

Helpful CLI utilities for querying and connecting to EC2 instances

https://github.com/FlipPath/ec2-cli-tools

ECDSA cryptographic signature library (pure python)

https://github.com/tlsfuzzer/python-ecdsa

Python 3.4 Enum backported to 3.3, 3.2, 3.1, 2.7

https://pypi.org/project/enum34/

Distributed Python deployment and communication

https://codespeak.net/execnet/

Scans log files and bans IP that makes too many password failures

https://www.fail2ban.org/wiki/index.php/Main_Page

Python package that provides useful locks

https://github.com/harlowja/fasteners

File I/O related functions and classes

http://www.livinglogic.de/Python/fileutils/

Code checking using pep8 and pyflakes

https://pypi.org/project/flake8/

Let your Python tests travel through time

https://github.com/spulec/freezegun

Python function signatures from PEP362

http://funcsigs.readthedocs.org/

Clean single-source support for Python 3 and 2

https://python-future.org/

Backport of the concurrent.futures package from Python 3.2

https://github.com/agronholm/pythonfutures

GData Python Client Library

https://github.com/google/gdata-python-client

Python bindings to the GNU dbm library (Python 3.10)

Python Extension that Wraps the GMP Library

http://code.google.com/p/gmpy/

Python bindings for GObject

Common files for the Python bindings for GObject

Python bindings for gstreamer

http://gstreamer.freedesktop.org/

Build System That Generates Other Build Systems

https://gyp.gsrc.io/

Classes and setuptools plugin for Mercurial repositories

https://github.com/jaraco/hgtools

Python based HTML parser based on the HTML5 spec

https://github.com/html5lib

Comprehensive HTTP client library

https://github.com/httplib2/httplib2

Featureful, correct URL for Python

https://github.com/python-hyper/hyperlink

Library for property based testing

https://hypothesis.works/ https://hypothesis.readthedocs.io/en/latest/ https://github.com/HypothesisWorks/hypothesis/tree/master/hypothesis-python

Internationalized Domain Names in Applications (IDNA)

https://github.com/kjd/idna

Python image size library

https://github.com/shibukawa/imagesize_py

Library that versions your Python projects

https://pypi.org/project/incremental/

Python 3.3's ipaddress for Python 2.6 and 2.7

https://pypi.org/project/ipaddress/