Although the parameter is called 'seq', the implementation shows that it
can be anything that can be passed to map(), which takes iterables:
0f42b726c8/Lib/subprocess.py (L565).
* Replace all uses of StrPath, BytesPath, and AnyPath in Python 2 stubs.
* Add StrOrBytesPath as preferred alias for AnyPath.
* Replace all remaining AnyPath instances with StrOrBytesPath.
* Mark AnyPath as obsolete.
Part of #5470
