code: def items(self):
      for name, value in super().items():
          if name == self.__class__._SINGLETON:
              if isinstance(value, self.value_type):
                  yield None, value
              else:
                  yield from value.items()
          elif isinstance(value, self.value_type):
              yield name, value
          else:
              assert isinstance(value, self.__class__)
              for subname, subvalue in value.items():
                  if subname is None:
                      yield name, subvalue
                  else:
                      yield "{}/{}".format(name, subname), subvalue
  
imports: from collections import OrderedDict
  from tensorforce import TensorforceError
label_desc: Use image node_id 11 for calling the NestedDict obj's underlying member method code with example usage: obj.items() without return types