code: def _get_inherited_field_types(class_to_field_type_overrides, schema_graph):
      
      inherited_field_type_overrides = dict()
      for superclass_name, field_type_overrides in class_to_field_type_overrides.items():
          for subclass_name in schema_graph.get_subclass_set(superclass_name):
              inherited_field_type_overrides.setdefault(subclass_name, dict())
              inherited_field_type_overrides[subclass_name].update(field_type_overrides)
      return inherited_field_type_overrides
docs: Return a dictionary describing the field type overrides in subclasses.