code: def test_round_trip_string_context(self):
      example = tf.train.SequenceExample()
      key = "string_feature"
      msu.set_string_context(b"test", example)
      self.assertEqual(b"test", msu.get_string_context(example))
      self.assertTrue(msu.has_string_context(example))
      self.assertEqual(
          b"test", example.context.feature[key].bytes_list.value[0]
      )
      msu.clear_string_context(example)
      self.assertFalse(msu.has_string_context(example))
      self.assertEqual("string_feature", msu.get_string_context_key())
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import tensorflow.compat.v1
  from mediapipe.util.sequence import media_sequence_util
label_desc: Use image node_id 10 for calling the MediaSequenceTest obj's underlying member method code with example usage: obj.test_round_trip_string_context() without return types