Super-fast templating language in Python

http://www.makotemplates.org/

Implements an RFC-5804 Manage Sieve client

https://bitbucket.org/ericvsmith/managesieve3

Python implementation of Markdown

https://pythonhosted.org/Markdown/

Fast and complete Python implementation of Markdown

http://code.google.com/p/python-markdown2/

Implements XML/HTML/XHTML Markup safe string for Python

https://github.com/pallets/markupsafe

Ned's script to check McCabe complexity

https://pypi.org/project/mccabe/

Python interface to Sendmail milter API

https://pythonhosted.org/milter/

Fastest markdown parser in pure Python

https://github.com/lepture/mistune

Rolling backport of unittest.mock for all Pythons

https://mock.readthedocs.org/en/latest/

Python 3 monotonic time module for Python 2

https://github.com/atdt/monotonic

More routines for operating on iterables, beyond itertools

https://github.com/more-itertools/more-itertools

Python MPD client library

https://pypi.org/project/python-mpd/

Python Library for Arbitrary-precision Floating-point Arithmetic

http://www.mpmath.org/

MessagePack (de)serializer for Python

https://msgpack.org/

Multidict implementation

https://github.com/aio-libs/multidict

Python-based audio metadata tag reader and writer

https://github.com/quodlibet/mutagen

Experimental type system extensions for programs

http://www.mypy-lang.org

Discovery-based unittest extension

https://nose.readthedocs.io/

Next generations of nicer testing for Python

https://nose2.readthedocs.io

Create NTLM authentication structures

https://github.com/jborean93/ntlm-auth

Python NTP library

https://pypi.org/project/ntplib/

The New Numeric Extension to Python

https://www.numpy.org/

Python library for OAuth version 1.0

https://github.com/joestump/python-oauth2

RFC-compliant implementation of the OAuth request-signing logic

https://github.com/idan/oauthlib

Python module to read MS OLE2 files

http://www.decalage.info/en/olefile

Python interface to the OpenSSL library

https://github.com/pyca/pyopenssl

Python wrapper for the OpenType Sanitizer

https://github.com/googlefonts/ots-python

Core utilities for Python packages

https://pypi.org/project/packaging/

Parameterized testing with any Python test framework

https://github.com/wolever/parameterized

Python SSH2 protocol library

https://www.paramiko.org/

Python module for parsing 'human readable' date/time expressions

https://github.com/bear/parsedatetime

Comprehensive password hashing framework supporting over 30 schemes

https://bitbucket.org/ecollins/passlib

Object-oriented filesystem paths

https://pypi.org/project/pathlib2/

Utility library for pattern matching of file paths

https://pypi.org/project/pathspec/

Python Build Reasonableness

https://github.com/openstack-dev/pbr

Pure-Python PDF toolkit

http://pybrary.net/pyPdf/

Pure-Python PDF toolkit

https://mstamy2.github.io/PyPDF2/

Pure Python Expect-like module

https://pexpect.readthedocs.io/

Pure-Python Interface to the PostgreSQL Database

https://github.com/tlocke/pg8000

Fork of the Python Imaging Library (PIL)

https://python-pillow.org/

Tool for installing and managing Python packages

https://pip.pypa.io/en/latest/

Importable pip API

https://github.com/di/pip-api

Interface Python with pkg-config

https://pypi.org/project/pkgconfig/

Query metadatdata from sdists / bdists / installed packages

https://pypi.org/project/pkginfo/

Plugin and hook calling mechanisms for Python

https://github.com/pytest-dev/pluggy

Python Lex-Yacc

http://www.dabeaz.com/ply/

Python PNG encoder/decoder

https://github.com/drj11/pypng

Collection of helpful Python tools

https://pypi.org/project/pockets/

Python library to parse and manage gettext catalogs

https://bitbucket.org/izi/polib/

Band-oriented PDF report generation from database query

http://newcenturycomputers.net/projects/pollyreports.html