code: def test_look_up_feature(self):
      feature_1 = text_format.Parse(
          """name: "feature1" """, schema_pb2.Feature()
      )
      feature_2 = text_format.Parse(
          """name: "feature2" """, schema_pb2.Feature()
      )
  
      container = [feature_1, feature_2]
      self.assertEqual(
          schema_util.look_up_feature("feature1", container), feature_1
      )
      self.assertEqual(
          schema_util.look_up_feature("feature2", container), feature_2
      )
      self.assertIsNone(
          schema_util.look_up_feature("feature3", container), None
      )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  from absl import flags
  from absl.testing import absltest
  from absl.testing import parameterized
  from tensorflow_data_validation import types
  from tensorflow_data_validation.utils import schema_util
  from google.protobuf import text_format
  from tensorflow_metadata.proto.v0 import schema_pb2
label_desc: Use image node_id 27 for calling the SchemaUtilTest obj's underlying member method code with example usage: obj.test_look_up_feature() without return types