Passing a set to Levenshtein_search.populate_wordset results in SystemError

[srkunze]

I ran into an issue trying out this package and passing in a set to populate_wordset.

wordset = Levenshtein_search.populate_wordset(-1, {'abc', 'abg'})

Somewhere later in the code, it failed:

Traceback (most recent call last):
  File "tst.py", line 38, in <module>
    for i, (dat, doc) in enumerate(zip(dats, docs)):
SystemError: ../Objects/listobject.c:169: bad argument to internal function

Would be great if either populate_wordset fails first or converts to list.

[srkunze]

populate_wordset also consumes dicts silently and break execution far later.