def format_time(t):
    """Format seconds into a human readable form."""
    m, s = divmod(t, 60)
    h, m = divmod(m, 60)
    d, h = divmod(h, 24)
    w, d = divmod(d, 7)
    if w:
        return '{0:2.0f}w{1:2.0f}d'.format(w, d)
    elif d:
        return '{0:2.0f}d{1:2.0f}h'.format(d, h)
    elif h:
        return '{0:2.0f}h{1:2.0f}m'.format(h, m)
    elif m:
        return '{0:2.0f}m{1:2.0f}s'.format(m, s)
    else:
        return '{0:5.0f}s'.format(s)
