Convenience method to get a copy of the structure, with options to add
        site properties.

        Returns:
            A copy of the Structure, with optionally new site_properties and
            optionally sanitized.

def copy(self):
        """
        Convenience method to get a copy of the structure, with options to add
        site properties.

        Returns:
            A copy of the Structure, with optionally new site_properties and
            optionally sanitized.
        """
        return GrainBoundary(self.lattice, self.species_and_occu, self.frac_coords,
                             self.rotation_axis, self.rotation_angle, self.gb_plane,
                             self.join_plane, self.init_cell, self.vacuum_thickness,
                             self.ab_shift, self.site_properties, self.oriented_unit_cell)