code: def testNotANumberPacked(self):
      golden_data = (
          "\xA2\x06\x04\x00\x00\xC0\x7F"
          "\xAA\x06\x08\x00\x00\x00\x00\x00\x00\xF8\x7F"
      )
      golden_message = unittest_pb2.TestPackedTypes()
      golden_message.ParseFromString(golden_data)
      self.assertTrue(isnan(golden_message.packed_float[0]))
      self.assertTrue(isnan(golden_message.packed_double[0]))
  
      serialized = golden_message.SerializeToString()
      message = unittest_pb2.TestPackedTypes()
      message.ParseFromString(serialized)
      self.assertTrue(isnan(message.packed_float[0]))
      self.assertTrue(isnan(message.packed_double[0]))
  
imports: import copy
  import math
  import operator
  import pickle
  import unittest
  from google.protobuf import unittest_import_pb2
  from google.protobuf import unittest_pb2
  from google.protobuf.internal import api_implementation
  from google.protobuf.internal import test_util
  from google.protobuf import message
label_desc: Use image node_id 12 for calling the MessageTest obj's underlying member method code with example usage: obj.testNotANumberPacked() without return types