def query_hek(time, time_window=1):
    """
    requests hek responses for a given time
    :param time: datetime object
    :param time_window: how far in hours on either side of the input time to look for results
    :return: hek response list
    """
    hek_client = hek.HEKClient()
    start_time = time - timedelta(hours=time_window)
    end_time = time + timedelta(hours=time_window)
    responses = hek_client.query(hek.attrs.Time(start_time, end_time))
    return responses