docs: def update(self, model_obj):
          """Update the entity record in the dictionary """
          identifier = model_obj[self.entity_cls.meta_.id_field.field_name]
          with self.conn['lock']:
              # Check if object is present
              if identifier not in self.conn['data'][self.schema_name]:
                  raise ObjectNotFoundError(
                      f'`{self.__class__.__name__}` object with identifier {identifier} '
                      f'does not exist.')
  
              self.conn['data'][self.schema_name][identifier] = model_obj
          return model_obj