CHAPTER ONE KEY TERMS • the Python Packaging Index is a public repository of open source licensed packages made available for use by other Python users • the Python Packaging Authority are the group of developers and documentation authors responsible for the maintenance and evolution of the standard packaging tools and the associated metadata and file format stan- dards. They maintain a variety of tools, documentation and issue trackers on both GitHub and Bitbucket. • $_{distutils}$is the original build and distribution system first added to the Python standard library in 1998. While direct use of$_{distutils}$is being phased out, it still laid the foundation for the current packaging and distribution infrastructure, and it not only remains part of the standard library, but its name lives on in other ways (such as the name of the mailing list used to coordinate Python packaging standards development). • setuptools is a (largely) drop-in replacement for$_{distutils}$first published in 2004. Its most notable addi- tion over the unmodified$_{distutils}$tools was the ability to declare dependencies on other packages. It is currently recommended as a more regularly updated alternative to$_{distutils}$that offers consistent support for more recent packaging standards across a wide range of Python versions. • wheel (in this context) is a project that adds the$_{bdist_wheel}$command to$_{distutils}$/setuptools. This produces a cross platform binary packaging format (called “wheels” or “wheel files” and defined in PEP 427 ) that allows Python libraries, even those including binary extensions, to be installed on a system without needing to be built locally. 3