def hr_time(seconds):
    """Formats a given time interval for human readability."""
    s = ''
    if seconds >= 86400:
        d = seconds // 86400
        seconds -= d * 86400
        s += f'{int(d)}d'
    if seconds >= 3600:
        h = seconds // 3600
        seconds -= h * 3600
        s += f'{int(h)}h'
    if seconds >= 60:
        m = seconds // 60
        seconds -= m * 60
        if 'd' not in s:
            s += f'{int(m)}m'
    if 'h' not in s and 'd' not in s:
        s += f'{int(seconds)}s'
    return s