code: def save(self,
               filename="phonopy_params.yaml",
               settings=None):
          
          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))
docs: 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}