code: def uint8_input_model():
      if not _HAS_TF_1:
          pytest.skip(MSG_TF1_NOT_FOUND)
      with tf.Graph().as_default() as graph:
          x = tf.placeholder(tf.uint8, shape=[10, 20], name="input")
          out = tf.add(x, tf.constant(5, dtype=tf.uint8), name="output")
      return graph
  
imports: import itertools
  import os
  import tempfile
  import numpy
  import pytest
  import coremltools
  from coremltools._deps import _HAS_TF_1, _HAS_TF_2, MSG_TF1_NOT_FOUND
  from coremltools.converters.mil.testing_reqs import backends, compute_units
  from coremltools.converters.mil.testing_utils import assert_cast_ops_count, assert_input_dtype, assert_ops_in_mil_program, assert_output_dtype, assert_prog_input_type, assert_prog_output_type, assert_spec_input_image_type, assert_spec_output_image_type, get_op_types_in_program, verify_prediction
  from coremltools.proto import FeatureTypes_pb2
  from coremltools.test.api.test_api_examples import TestInputs
label_desc: Use image node_id 1 for calling a global function with example usage: uint8_input_model() and returns: graph