Close #17932: Fix an integer overflow issue on Windows 64-bit in iterators:
change the C type of seqiterobject.it_index from long to Py_ssize_t.
Reuse Py_MIN and Py_MAX macros: remove duplicate MIN/MAX macros

multiprocessing.h: remove unused MIN and MAX macros
Tweak at the suggestion of Ezio Melotti for exception messages when
EOF is hit while trying to read the header of a bytecode file.
merge
Issue #9566: Fix compiler warning on Windows 64-bit in _bz2module.c
Close #17931: Fix PyLong_FromPid() on Windows 64-bit: processes are identified
by their HANDLE which is a pointer (and not a long, which is smaller).