The lxml XML toolkit is a Pythonic binding for the C libraries libxml2 and libxslt.

Pluggy is an extraction of the plugin manager as used by Pytest but stripped of Pytest specific details.

This is a backport of the subprocess standard library module from Python 3.2 and 3.3 for use on Python 2. It includes bugfixes and some new features. On POSIX systems it is guaranteed to be reliable when used in threaded applications. It includes timeout support from Python 3.3 but otherwise matches 3.2’s API.

This package provides a pathlib-compatible Zipfile object wrapper. It provides a backport of the Path object.

Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. It aims to provide selecting, matching, and filtering using modern CSS selectors. Soup Sieve currently provides selectors from the CSS level 1 specifications up through the latest CSS level 4 drafts and beyond (though some are not yet implemented).

Pysam is a Python module for reading and manipulating files in the SAM/BAM format. Pysam is a lightweight wrapper of the SAMtools C API. It also includes an interface for tabix.

This module is primarily a backport of the Python 3.2 contextlib to earlier Python versions. Like contextlib, it provides utilities for common tasks involving decorators and context managers. It also contains additional features that are not part of the standard library.

Enum34 is the new Python stdlib enum module available in Python 3.4 backported for previous versions of Python from 2.4 to 3.3.

Beautiful Soup is a Python library designed for rapidly setting up screen-scraping projects. It offers Pythonic idioms for navigating, searching, and modifying a parse tree, providing a toolkit for dissecting a document and extracting what you need. It automatically converts incoming documents to Unicode and outgoing documents to UTF-8.

Pycairo is a set of Python bindings for the Cairo graphics library.

This module is primarily a backport of the Python 3.2 contextlib to earlier Python versions. Like contextlib, it provides utilities for common tasks involving decorators and context managers. It also contains additional features that are not part of the standard library.

The goal of pathlib2 is to provide a backport of standard pathlib module which tracks the standard library module, so all the newest features of the standard pathlib can be used also on older Python versions.

Pathlib offers a set of classes to handle file system paths. It offers the following advantages over using string objects:

1. No more cumbersome use of os and os.path functions. Everything can be done easily through operators, attribute accesses, and method calls.

2. Embodies the semantics of different path types. For example, comparing Windows paths ignores casing.

3. Well-defined semantics, eliminating any inconsistencies or ambiguities (forward vs. backward slashes, etc.).

The Python Imaging Library adds image processing capabilities to your Python interpreter. This library provides extensive file format support, an efficient internal representation, and fairly powerful image processing capabilities. The core image library is designed for fast access to data stored in a few basic pixel formats. It should provide a solid foundation for a general image processing tool.

Thin-wrapper around the mock package for easier use with pytest

importlib_metadata is a library which provides an API for accessing an installed Python package's metadata, such as its entry points or its top-level name. This functionality intends to replace most uses of pkg_resources entry point API and metadata API. Along with importlib.resources in Python 3.7 and newer, this can eliminate the need to use the older and less efficient pkg_resources package.

This package is a backport of the functools module from Python 3.2.3 for use with older versions of Python and PyPy.

Mock is a library for testing in Python. It allows you to replace parts of your system under test with mock objects and make assertions about how they have been used. This library is now part of Python (since Python 3.3), available via the unittest.mock module.

Pyro is a Distributed Object Technology system written in Python that is designed to be easy to use. It resembles Java's Remote Method Invocation (RMI). It has less similarity to CORBA, which is a system and language independent Distributed Object Technology and has much more to offer than Pyro or RMI. Pyro 3.x is no longer maintained. New projects should use Pyro4 instead, which is the new Pyro version that is actively developed.

The goal of pathlib2 is to provide a backport of standard pathlib module which tracks the standard library module, so all the newest features of the standard pathlib can be used also on older Python versions.

Pathlib offers a set of classes to handle file system paths. It offers the following advantages over using string objects:

1. No more cumbersome use of os and os.path functions. Everything can be done easily through operators, attribute accesses, and method calls.

2. Embodies the semantics of different path types. For example, comparing Windows paths ignores casing.

3. Well-defined semantics, eliminating any inconsistencies or ambiguities (forward vs. backward slashes, etc.).

Six is a Python 2 and 3 compatibility library. It provides utility functions for smoothing over the differences between the Python versions with the goal of writing Python code that is compatible on both Python versions. Six supports every Python version since 2.5. It is contained in only one Python file, so it can be easily copied into your project.

Pytest-cov produces coverage reports. It supports centralised testing and distributed testing in both load and each modes. It also supports coverage of subprocesses.

This package provides a Python library intended for use in automated tests. One difficulty when testing software is that the code under test might need to read or write to files in the local file system. If the file system is not set up in just the right way, it might cause a spurious error during the test. The pyfakefs library provides a solution to problems like this by mocking file system interactions. In other words, it arranges for the code under test to interact with a fake file system instead of the real file system. The code under test requires no modification to work with pyfakefs.

importlib_metadata is a library which provides an API for accessing an installed Python package's metadata, such as its entry points or its top-level name. This functionality intends to replace most uses of pkg_resources entry point API and metadata API. Along with importlib.resources in Python 3.7 and newer, this can eliminate the need to use the older and less efficient pkg_resources package.

Setuptools_scm handles managing your Python package versions in software configuration management (SCM) metadata instead of declaring them as the version argument or in a SCM managed file.