(self, start=None)
return self._accumulate(aggregations.GroupbySum, start=start)
Groupby-sum

        Parameters
        ----------
        start: None or resulting Python object type from the operation
            Accepts a valid start state.
Groupby-sum
Groupby - sum
def sum(self, start=None):
        """ Groupby-sum

        Parameters
        ----------
        start: None or resulting Python object type from the operation
            Accepts a valid start state.

        """
        return self._accumulate(aggregations.GroupbySum, start=start)
def sum ( self , start = None ) : return self . _accumulate ( aggregations . GroupbySum , start = start )