code: def _get_extension_by_field(self, name):
          
          if name is None:
              raise TypeError("Expected field name")
  
          # Reuse existing lookups.
          tr_model = self.get_model_by_field(name)
          for meta in self._extensions:
              if meta.model == tr_model:
                  return meta
docs: Find the ParlerOptions object that corresponds with the given translated field.