Greetings,

tl;dr:
Need to remove npy_3kcompat.h from any source code location since
Python2 is no longer supported.

Background:
Ran into an error after compiling various apps regarding
npy_PyErr_ChainExceptionsCause() being undefined at runtime.

Poking around shows that this is related to npy_3kcompat.h, which
seems to be for Python2 compatibility.
(There is a differently named counterpart for Python3.)

This seems to be used in a couple of numpy/core/src/multiarray files.

Seems that since Python2 is no longer supported, cleaning up cruft of
P2 will improve code and should eliminate the problem I ran into, (or
else move an error report to something else...)

Is this reasonable to eliminate?