chokes under 3.7 on MacOS

[kjappelbaum]

spotted in the mofchecker CI, can be reproduced in clean 3.7 env on MacOS

>>> from pyeqeq.main import run_on_cif
>>> run_on_cif('/Users/kevinmaikjablonka/Downloads/cifs_cellopt/20540N2_ddec.cif')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/kevinmaikjablonka/opt/miniconda3/envs/eqeq/lib/python3.7/site-packages/pyeqeq/main.py", line 40, in run_on_cif
    with pyeqeq_eqeq.ostream_redirect(stdout=True, stderr=True):
AttributeError: module 'pyeqeq_eqeq' has no attribute 'ostream_redirect'

does not occur on 3.7/3.8 on Linux and 3.8 on Mac