code: def testLoadOpFromSignatureDef(self):
      # Force the test to run in graph mode.
      # This tests a deprecated v1 API that uses functionality that does not work
      # with eager tensors (namely build_tensor_info_from_op).
      with ops.Graph().as_default():
          key = "adding_1_and_2_key"
          add_op = math_ops.add(1, 2, name="adding_1_and_2")
          signature_def = signature_def_utils_impl.op_signature_def(
              add_op, key
          )
          self.assertEqual(
              add_op,
              signature_def_utils_impl.load_op_from_signature_def(
                  signature_def, key
              ),
          )
  
imports: from tensorflow.core.framework import types_pb2
  from tensorflow.core.protobuf import meta_graph_pb2
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import ops
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.platform import test
  from tensorflow.python.saved_model import signature_constants
  from tensorflow.python.saved_model import signature_def_utils_impl
  from tensorflow.python.saved_model import utils
label_desc: Use image node_id 19 for calling the SignatureDefUtilsTest obj's underlying member method code with example usage: obj.testLoadOpFromSignatureDef() without return types