def prettyTime(t):
    """ prettyTime(t): input t comes in as seconds. Output is a str
    with units attached (secs, mins, hrs, etc.)
    """
    if t < 120:
        return '%.2f secs' % (t)
    t = t / 60.0
    if t < 120:
        return '%.2f mins' % (t)
    t = t / 60.0
    if t < 25:
        return '%.2f hrs' % (t)
    t = t / 24.0
    if t < 28:
        return '%.2f days' % (t)
    t = t / 7.0
    return '%.2f weeks' % (t)