Update setuptools to 49.0.0

[pyup-bot]

This PR updates setuptools from 47.3.1 to 49.0.0.

Changelog

49.0.0

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* 2165: Setuptools no longer installs a site.py file during easy_install or develop installs. As a result, .eggs on PYTHONPATH will no longer take precedence over other packages on sys.path. If this issue affects your production environment, please reach out to the maintainers at 2165.
* 2137: Removed (private) pkg_resources.RequirementParseError, now replaced by packaging.requirements.InvalidRequirement. Kept the name for compatibility, but users should catch InvalidRequirement instead.
* 2180: Update vendored packaging in pkg_resources to 19.2.
* 2199: Fix exception causes all over the codebase by using ``raise new_exception from old_exception``

48.0.0

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* 2143: Setuptools adopts distutils from the Python 3.9 standard library and no longer depends on distutils in the standard library. When importing ``setuptools`` or ``setuptools.distutils_patch``, Setuptools will expose its bundled version as a top-level ``distutils`` package (and unload any previously-imported top-level distutils package), retaining the expectation that ``distutils``' objects are actually Setuptools objects. Although this change is not expected to break any use cases, it will likely affect tool chains that are monkey-patching distutils or relying on Setuptools' own monkey-patching of distutils.

47.3.2

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* 2071: Replaced references to the deprecated imp package with references to importlib

Links

• PyPI: https://pypi.org/project/setuptools
• Changelog: https://pyup.io/changelogs/setuptools/
• Repo: https://github.com/pypa/setuptools

[duckinator]

bors r+

[bors]

Build succeeded:

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