code: def get_branding_metadata(self):
          
          metadata = dict(self._branding_metadata)
          metadata.update({'existing_id_values': self.my_osid_object_form._my_map['brandingIds']})
          return Metadata(**metadata)
docs: Gets the metadata for the asset branding.
  
          return: (osid.Metadata) - metadata for the asset branding.
          *compliance: mandatory -- This method must be implemented.*