docs: def verify_retry_data(self, retry_data):
          '''
          verifies the specified retry data
          '''
          retry_defaults = {
                  'until': True,
                  'attempts': 2,
                  'splay': 0,
                  'interval': 30,
          }
          expected_data = {
              'until': bool,
              'attempts': int,
              'interval': int,
              'splay': int,
          }
          validated_retry_data = {}
          if isinstance(retry_data, dict):
              for expected_key, value_type in six.iteritems(expected_data):
                  if expected_key in retry_data:
                      if isinstance(retry_data[expected_key], value_type):
                          validated_retry_data[expected_key] = retry_data[expected_key]
                      else:
                          log.warning(
                              'An invalid value was passed for the retry %s, '
                              'using default value \'%s\'',
                              expected_key, retry_defaults[expected_key]
                          )
                          validated_retry_data[expected_key] = retry_defaults[expected_key]
                  else:
                      validated_retry_data[expected_key] = retry_defaults[expected_key]
          else:
              log.warning(('State is set to retry, but a valid dict for retry '
                           'configuration was not found.  Using retry defaults'))
              validated_retry_data = retry_defaults
          return validated_retry_data