def save_model(self, fname, include_unsigned_edges=False):
        """Save the assembled model's SIF string into a file.

        Parameters
        ----------
        fname : str
            The name of the file to save the SIF into.
        include_unsigned_edges : bool
            If True, includes edges with an unknown activating/inactivating
            relationship (e.g., most PTMs). Default is False.
        """
        sif_str = self.print_model(include_unsigned_edges)
        with open(fname, 'wb') as fh:
            fh.write(sif_str.encode('utf-8'))
Save the assembled model's SIF string into a file.

        Parameters
        ----------
        fname : str
            The name of the file to save the SIF into.
        include_unsigned_edges : bool
            If True, includes edges with an unknown activating/inactivating
            relationship (e.g., most PTMs). Default is False.