code: def export_simple_graph(self, builder_cls):
      g, sig_def_map, _ = build_graph_helper()
      with session.Session(graph=g) as sess:
          self.evaluate(variables.global_variables_initializer())
          builder = builder_cls(SIMPLE_ADD_SAVED_MODEL)
          builder.add_meta_graph_and_variables(
              sess, ["foo_graph"], sig_def_map
          )
          builder.save()
  
imports: import os
  import shutil
  from absl.testing import parameterized
  from tensorflow.python.client import session
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import control_flow_ops
  from tensorflow.python.ops import resource_variables_toggle
  from tensorflow.python.ops import state_ops
  from tensorflow.python.ops import variable_v1
  from tensorflow.python.ops import variables
  from tensorflow.python.platform import test
  from tensorflow.python.saved_model import builder
  from tensorflow.python.saved_model import loader_impl
  from tensorflow.python.saved_model import signature_def_utils
  from tensorflow.python.saved_model import utils
  from tensorflow.python.training import saver
label_desc: Use image node_id 1 for calling the SavedModelLoaderTest obj's underlying member method code with example usage: obj.export_simple_graph(builder_cls) without return types