<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def save(self, filename="phonopy_params.yaml", settings=None):
 """Save parameters in Phonopy instants into file. Parameters filename: str, optional File name. Default is "phonopy_params.yaml" settings: dict, optional It is described which parameters are written out. Only the settings expected to be updated from the following default settings are needed to be set in the dictionary. The possible parameters and their default settings are: {'force_sets': True, 'displacements': True, 'force_constants': False, 'born_effective_charge': True, 'dielectric_constant': True} """

        phpy_yaml = PhonopyYaml(calculator=self._calculator,
                                settings=settings)
        phpy_yaml.set_phonon_info(self)
        with open(filename, 'w') as w:
            w.write(str(phpy_yaml))