def _build_groupby(self, by: List[Union[('Series', Label)]], as_index: bool, dropna: bool) -> 'DataFrameGroupBy':
    from pyspark.pandas.groupby import DataFrameGroupBy
    return DataFrameGroupBy._build(self, by, as_index=as_index, dropna=dropna)
def _build_groupby(self, by: List[Union[('Series', Label)]], as_index: bool, dropna: bool) -> 'DataFrameGroupBy':
    from pyspark.pandas.groupby import DataFrameGroupBy
    return DataFrameGroupBy._build(self, by, as_index=as_index, dropna=dropna)