code: def get_acl_helper(self, key_name, headers, query_args):
          
          response = self.connection.make_request('GET', self.name, key_name,
                                                  query_args=query_args, 
                                                  headers=headers)
          body = response.read()
          if response.status == 200:
              acl = ACL(self)
              h = handler.XmlHandler(acl, self)
              xml.sax.parseString(body, h)
              return acl
          else:
              raise self.connection.provider.storage_response_error(
                  response.status, response.reason, body)
docs: provides common functionality for get_acl() and get_def_acl()