Returns information about a long-running task.
        :param long_task_id (string): The key of the task to be returned.
        :param expand (string): A comma separated list of properties to expand on the task. Default: Empty
        :param callback: OPTIONAL: The callback to execute on the resulting data, before the method returns.
                         Default: None (no callback, raw data returned).
        :return: The JSON data returned from the longtask/{id} endpoint,
                 or the results of the callback. Will raise requests.HTTPError on bad input, potentially.

def get_long_task_info(self, long_task_id, expand=None, callback=None):
        """
        Returns information about a long-running task.
        :param long_task_id (string): The key of the task to be returned.
        :param expand (string): A comma separated list of properties to expand on the task. Default: Empty
        :param callback: OPTIONAL: The callback to execute on the resulting data, before the method returns.
                         Default: None (no callback, raw data returned).
        :return: The JSON data returned from the longtask/{id} endpoint,
                 or the results of the callback. Will raise requests.HTTPError on bad input, potentially.
        """
        params = {}
        if expand:
            params["expand"] = expand
        return self._service_get_request("rest/api/longtask/{id}".format(id=long_task_id), params=params,
                                         callback=callback)