Mark the easy_install script and setuptools command as deprecated, and use `pip <https://pip.pypa.io/en/stable/>`_ when available to fetch/build wheels for missing ``setup_requires``/``tests_require`` requirements, with the following differences in behavior:
* support for ``python_requires``
* better support for wheels (proper handling of priority with respect to PEP 425 tags)
* PEP 517/518 support
* eggs are not supported
* no support for the ``allow_hosts`` easy_install option (``index_url``/``find_links`` are still honored)
* pip environment variables are honored (and take precedence over easy_install options)
Setuptools now exposes a new entry point hook "setuptools.finalize_distribution_options", enabling plugins like `setuptools_scm <https://pypi.org/project/setuptools_scm>`_ to configure options on the distribution at finalization time.
Mark the easy_install script and setuptools command as deprecated, and use `pip <https://pip.pypa.io/en/stable/>`_ when available to fetch/build wheels for missing ``setup_requires``/``tests_require`` requirements, with the following differences in behavior:
* support for ``python_requires``
* better support for wheels (proper handling of priority with respect to PEP 425 tags)
* PEP 517/518 support
* eggs are not supported
* no support for the ``allow_hosts`` easy_install option (``index_url``/``find_links`` are still honored)
* pip environment variables are honored (and take precedence over easy_install options)