def pretty_time_delta(seconds):
    sign_string = '-' if seconds < 0 else ''
    seconds = abs(int(seconds))
    days, seconds = divmod(seconds, 86400)
    hours, seconds = divmod(seconds, 3600)
    minutes, seconds = divmod(seconds, 60)
    if days > 0:
        return '%s%dd%dh%dm%ds' % (sign_string, days, hours, minutes, seconds)
    elif hours > 0:
        return '%s%dh%dm%ds' % (sign_string, hours, minutes, seconds)
    elif minutes > 0:
        return '%s%dm%ds' % (sign_string, minutes, seconds)
    else:
        return '%s%ds' % (sign_string, seconds)