def ms_to_hours(milliseconds):
    """Convert milliseconds into format (h)h:mm:ss"""
    seconds = milliseconds / 1000
    minutes = seconds // 60
    seconds -= minutes * 60
    hours = minutes // 60
    minutes -= hours * 60
    if minutes < 10:
        minutes = '0' + str(int(minutes))
    else:
        minutes = str(int(minutes))
    if seconds < 10:
        seconds = '0' + str(int(seconds))
    else:
        seconds = str(int(seconds))
    return f'{int(hours)}:{minutes}:{seconds}'