def save_model(self, path, output_format=None):
        """Save the :class:`pybel.BELGraph` using one of the outputs from
        :py:mod:`pybel`

        Parameters
        ----------
        path : str
            The path to output to
        output_format : Optional[str]
            Output format as ``cx``, ``pickle``, ``json`` or defaults to ``bel``
        """
        if output_format == 'pickle':
            pybel.to_pickle(self.model, path)
        else:
            with open(path, 'w') as fh:
                if output_format == 'json':
                    pybel.to_json_file(self.model, fh)
                elif output_format == 'cx':
                    pybel.to_cx_file(self.model, fh)
                else: # output_format == 'bel':
                    pybel.to_bel(self.model, fh)
Save the :class:`pybel.BELGraph` using one of the outputs from
        :py:mod:`pybel`

        Parameters
        ----------
        path : str
            The path to output to
        output_format : Optional[str]
            Output format as ``cx``, ``pickle``, ``json`` or defaults to ``bel``