code: def layout_json_schema(self):
          
          if self._layout_json_schema is None and self.layout_json_schema_file is not None:
              if os.path.isfile(self.layout_json_schema_file):
                  with open(self.layout_json_schema_file) as fh:
                      self._layout_json_schema = json.load(fh)
          return self._layout_json_schema
docs: Load layout.json schema file.