code: def testMergeAllFields(self):
      message = unittest_pb2.TestAllTypes()
      test_util.SetAllFields(message)
      ascii_text = text_format.MessageToString(message)
  
      parsed_message = unittest_pb2.TestAllTypes()
      text_format.Merge(ascii_text, parsed_message)
      self.assertEqual(message, parsed_message)
      test_util.ExpectAllFieldsSet(self, message)
  
imports: import difflib
  import re
  import unittest
  from google.protobuf import text_format
  from google.protobuf.internal import test_util
  from google.protobuf import unittest_pb2
  from google.protobuf import unittest_mset_pb2
label_desc: Use image node_id 20 for calling the TextFormatTest obj's underlying member method code with example usage: obj.testMergeAllFields() without return types