def convert_ms(ms):
    """
    Converts milliseconds into h:m:s

    :param ms: int
    :return: str
    """
    seconds = ms / 1000 % 60
    seconds = int(seconds)
    if seconds < 10:
        seconds = '0' + str(seconds)
    else:
        seconds = str(seconds)
    minutes = ms / (1000 * 60) % 60
    minutes = int(minutes)
    if minutes < 10:
        minutes = '0' + str(minutes)
    else:
        minutes = str(minutes)
    hours = ms / (1000 * 60 * 60) % 24
    hours = int(hours)
    if hours < 10:
        hours = '0' + str(hours)
    else:
        hours = str(hours)
    return hours + ':' + minutes + ':' + seconds
