code: def get_container_containers(self, path):
          
          container = self.get_container(path)
          containers = {}
          for name,value in container._values.items():
              if isinstance(value, ValueTree):
                  containers[name] = value
          return containers
docs: :param path: str or Path instance
          :return:
          :rtype: dict[str,ValueTree]
          :raises ValueError: A component of path is a field name.
          :raises KeyError: A component of path doesn't exist.