GroupBy.rank with "TypeError: 'NoneType' object is not ...
github.com › pandas-dev › pandasAug 22, 2019 · TypeError: 'NoneType' object is not callable After debugging the file I find the Error breakout in ops.py >_get_cython_function > func = afunc = get_func(ftype['name']) (line 390), return fun get a None Object. if I use "getattr(libgroupby, 'group_rank')(line 376)" I find that "AttributeError: module 'pandas._libs.groupby' has no attribute 'group_rank'"