def standard_time(yyyymmddhhmmss):
    """Return date in form yyyy-mm-ddTHH:MM:SSZ such as 2012-08-11T16:21:00Z"""
    
    s = yyyymmddhhmmss
    return "%s-%s-%sT%s:%s:%sZ" % (s[0:4], s[4:6], s[6:8], s[8:10], s[10:12], s[12:14])