TODO: use more_itertools.peekable instead
        :return: The current result item.
        :rtype: dict. 
        :raises StopIteration: If there is no current item.

def peek(self):
        """
        TODO: use more_itertools.peekable instead
        :return: The current result item.
        :rtype: dict. 
        :raises StopIteration: If there is no current item.
            
        """
        if self._cur_item is None:
            self._cur_item = next(self._ex_context)

        return self._cur_item