old_contents: from unittest2 import TestCase
  from mock import patch, Mock
  
  
  class Util(TestCase):
      def test_something(self):
          pass
  
new_contents: from botocore.exceptions import ClientError
  from unittest2 import TestCase
  from mock import patch, Mock
  
  from simple_container_runtime import util
  
  
  class Util(TestCase):
      def test_with_boto_retry_retries_method_call_for_throttling_exception(self):
          count_func = Mock()
  
          @util.with_boto_retry(max_retries=1, pause_time_multiplier=1)
          def my_retried_method(count_func):
              count_func()
              exception = ClientError(error_response={"Error": {"Code": "Throttling", "Message": "Rate exceeded"}},
                                      operation_name="DescribeStacks")
              raise exception
  
          with self.assertRaises(ClientError):
              my_retried_method(count_func)
  
          self.assertEqual(2, count_func.call_count)
  
      def test_with_boto_retry_does_not_retry_for_simple_exception(self):
          count_func = Mock()
  
          @util.with_boto_retry(max_retries=1, pause_time_multiplier=1)
          def my_retried_method(count_func):
              count_func()
              raise Exception
  
          with self.assertRaises(Exception):
              my_retried_method(count_func)
  
          self.assertEqual(1, count_func.call_count)
  
      def test_with_boto_retry_does_not_retry_for_another_boto_client_error(self):
          count_func = Mock()
  
          @util.with_boto_retry(max_retries=1, pause_time_multiplier=1)
          def my_retried_method(count_func):
              count_func()
              exception = ClientError(error_response={"Error": {"Code": "Another Error", "Message": "Foo"}},
                                      operation_name="DescribeStacks")
              raise exception
  
          with self.assertRaises(ClientError):
              my_retried_method(count_func)
  
          self.assertEqual(1, count_func.call_count)
  
      def test_with_boto_retry_does_not_retry_without_exception(self):
          count_func = Mock()
  
          @util.with_boto_retry(max_retries=1, pause_time_multiplier=1)
          def my_retried_method(count_func):
              count_func()
              return "foo"
  
          self.assertEqual("foo", my_retried_method(count_func))
          self.assertEqual(1, count_func.call_count)
  
subject: add some tests for boto_retry wrapper