get information about this term

        Parameters
        ----------

        Returns
        -------
        dict containing information to duplicate this term

def info(self):
        """get information about this term

        Parameters
        ----------

        Returns
        -------
        dict containing information to duplicate this term
        """
        info = super(TensorTerm, self).info
        info.update({'terms':[term.info for term in self._terms]})
        return info