def time_string(seconds):
    """Converts time in seconds to a fixed-width string format."""
    days, rem = divmod(int(seconds), 24 * 3600)
    hrs, rem = divmod(rem, 3600)
    mins, secs = divmod(rem, 60)
    return "{0:02},{1:02}:{2:02}:{3:02}".format(days, hrs, mins, secs)