Invoked as a response to the StackExchange API request. Will decode
        the response and set the result for the future to return the callback or
        raise an exception

def _on_stackexchange_request(self, future, response):
        """Invoked as a response to the StackExchange API request. Will decode
        the response and set the result for the future to return the callback or
        raise an exception

        """
        content = escape.json_decode(response.body)
        if 'error' in content:
            future.set_exception(Exception('StackExchange error: %s' %
                                           str(content['error'])))
            return
        future.set_result(content)