docs: def get_name_for(self, dynamic_part):
          """
          Compute the name of the variation of the current dynamic field based on
          the given dynamic part. Use the "format" attribute to create the final
          name.
          """
          name = self.format % dynamic_part
          if not self._accept_name(name):
              raise ImplementationError('It seems that pattern and format do not '
                                        'match for the field "%s"' % self.name)
          return name