code: def _choice_getter(self):
          
          def get_group_member_element(obj):
              return obj.first_child_found_in(*self._member_nsptagnames)
          get_group_member_element.__doc__ = (
              'Return the child element belonging to this element group, or '
              '|None| if no member child is present.'
          )
          return get_group_member_element
docs: Return a function object suitable for the "get" side of the property
          descriptor.