Log Message:
py-magic: updated to 0.4.22

Changes to 0.4.21, 0.4.22

 - Unify dll loader between the standard and compat library, fixing load
 failures on some previously supported platforms.

Changes to 0.4.20

- merge in a compatability layer for the upstream libmagic python binding.
  Since both this package and that one are called 'magic', this compat layer
  removes a very common source of runtime errors.  Use of that libmagic API will
  produce a deprecation warning.

- support python 3.9 in tests and pypi metadata

- add support for magic_descriptor functions, which take a file descriptor
  rather than a filename.

- sometimes the returned description includes snippets of the file, e.g a title
  for MS Word docs.  Since this is in an unknown encoding, we would throw a
  unicode decode error trying to decode.  Now, it decodes with
  'backslashreplace' to handle this more gracefully.  The undecodable characters
  are replaced with hex escapes.

- add support for MAGIC_EXTENSION, to return possible file extensions.

- add mypy typing stubs file, for type checking