setup.py: Fix debian unstable package build
Since Python 3.10, support for PyArg_ParseTuple() # formats requires PY_SSIZE_T_CLEAN macro to be defined.
See https://github.com/python/cpython/issues/85115
Migrated from D8491 (view on Phabricator)
Staging instance, all changes can be removed at any time
Since Python 3.10, support for PyArg_ParseTuple() # formats requires PY_SSIZE_T_CLEAN macro to be defined.
See https://github.com/python/cpython/issues/85115
Migrated from D8491 (view on Phabricator)