old_contents: from hedgehog.utils.protobuf import MessageType, Message
  from .proto.test_pb2 import TestMessage, Test
  
  
  TestMessageType = MessageType(TestMessage)
  parse = TestMessageType.parse
  
  
  @TestMessageType.register(Test, 'test')
  class Test(Message):
      def __init__(self, field):
          self.field = field
  
      @classmethod
      def _parse(cls, msg):
          return cls(msg.field)
  
      def _serialize(self, msg):
          msg.field = self.field
  
new_contents: from hedgehog.utils.protobuf import MessageType, Message
  from .proto import test_pb2
  
  
  TestMessageType = MessageType(test_pb2.TestMessage)
  parse = TestMessageType.parse
  
  
  @TestMessageType.register(test_pb2.Test, 'test')
  class Test(Message):
      def __init__(self, field):
          self.field = field
  
      @classmethod
      def _parse(cls, msg):
          return cls(msg.field)
  
      def _serialize(self, msg):
          msg.field = self.field
  
subject: change imports in test code