@abstractmethod
def _build_groupby(self: FrameLike, by: List[Union[('Series', Tuple)]], as_index: bool, dropna: bool) -> 'GroupBy[FrameLike]':
    pass
@abstractmethod
def _build_groupby(self: FrameLike, by: List[Union[('Series', Tuple)]], as_index: bool, dropna: bool) -> 'GroupBy[FrameLike]':
    pass