code: def __init__(self, name: Optional[str] = None) -> None:
      super().__init__(name)
      self.submodule_list = [A(), A()]
      self.submodule_dict = dict(a=A(), b=A())
      self.var_trainable = tf.Variable(
          tf.zeros((2, 2, 1)), trainable=True
      )
      self.var_fixed = tf.Variable(tf.ones((2, 2, 1)), trainable=False)
  
imports: from typing import Any, Callable, Mapping, Optional, Type
  import numpy
  import pytest
  import tensorflow
  from _pytest.fixtures import SubRequest
  from packaging.version import Version
  import gpflow
  from gpflow.base import AnyNDArray
  from gpflow.config import Config, as_context
  from gpflow.utilities import set_trainable
  from gpflow.utilities.traversal import _merge_leaf_components, leaf_components, tabulate_module_summary
label_desc: Use image node_id 1 to create a new B object from inherited base classes: tf with example: obj = B(name)