def []=(key, value)
      return super if has_key?(key)
      alt = alternate_key(key)
      has_key?(alt) ? super(alt, value) : super
    end
def []=(key, value)
      return super if has_key?(key)
      alt = alternate_key(key)
      has_key?(alt) ? super(alt, value) : super
    end
Returns the property value for the key. If there is no key entry but there is an
 alternate key entry, then alternate key entry is set.