Series.str.count(pat, flags=0, **kwargs)

Series.notnull()

pandas.merge(left, right, how='inner', on=None, left_on=None, right_on=None, left_index=False, right_index=False, sort=False, suffixes=('_x', '_y')

Panel4D.notnull()

Panel4D.interpolate(method='linear', axis=0, limit=None, inplace=False, limit_direction='forward', downcast=None, **kwargs)

Series.ffill(axis=None, inplace=False, limit=None, downcast=None)

CategoricalIndex.intersection(other)

MultiIndex.to_datetime(dayfirst=False)

CategoricalIndex.get_indexer_for(target, **kwargs)

Series.sem(axis=None, skipna=None, level=None, ddof=1, numeric_only=None, **kwargs)