AttributeError with psoap.matrix_functions

[megbedell]

Hi! I'm trying to use PSOAP and running into an error when trying to execute psoap_retrieve_SB2.py:
AttributeError: module 'psoap.matrix_functions' has no attribute 'fill_V11_f'

I tried to import psoap.matrix_functions and call each of the expected functions myself and got the same error for all four function names. Seems like maybe there was an issue with the Cython at install..? Both psoap-initialize --check and py.test pass with no errors though.

Any debugging advice would be appreciated!