def METHOD_NAME (self, other=None) :
    """
    clone()
    Implements deep copy. u
    Unlike the default python assignment (copy object reference),
    a deep copy will create a new object instance with the same state --
    after a deep copy, a change on one instance will not affect the other.
    """
    # a job description only has attributes - so create a new instance,
    # clone the attribs, and done.
    if not other :
        other = Description ()
    return self._attributes_deep_copy (other)