In Python 3.9+, `PyCFunction_New` and `PyCFunction_NewEx` are themselves
macros around `PyMethod_New`. To fix the warning, both macros need to
be untouched for those Python versions, instead the actual function
`PyMethod_New` needs to be imported and aliased.
This commit:
- Adds the import of the `PyCMethod_New` symbol
- Adds the function definition for `Import_PyCMethod_New`
- Adds the `PyCMethod_New` function alias
8d0131c519