def _displayDuration(start, end):
    """
        Display a human-readable time duration.

        :param start:   Time at the start
        :param end:     Time at the end
        :return:        The duration ``end - start``
    """
    duration = end - start
    days = duration.days
    hours = duration.seconds // 3600
    minutes = (duration.seconds % 3600) // 60
    seconds = (duration.seconds % 60)

    print("Time at start:       {}\n"
          "Time at end:         {}\n"
          "Elapsed time:        {} days, {} hours, {} minutes, {} seconds".format(start, end, days, hours, minutes, seconds))

    return duration