cannot run from csv without pretrust file

[hypnagonia]

scores = a.run_eigentrust_from_csv('examples/lt.csv')
print(scores)

throws

  File "/Users/jenya/IdeaProjects/karma/august-prototypes/dry_run.py", line 33, in <module>
    scores = a.run_eigentrust_from_csv('examples/lt.csv')
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/jenya/IdeaProjects/karma/august-prototypes/openrank_sdk/eigentrust_client.py", line 517, in run_eigentrust_from_csv
    pt_url = 'file:' + os.path.realpath(pretrust_filename)
                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "<frozen posixpath>", line 434, in realpath
TypeError: expected str, bytes or os.PathLike object, not NoneType