Create a L{NamedLayer} in this SLD.

        @type  name: string
        @param name: The name of the layer.
        @rtype: L{NamedLayer}
        @return: The named layer, attached to this SLD.

def create_namedlayer(self, name):
        """
        Create a L{NamedLayer} in this SLD.

        @type  name: string
        @param name: The name of the layer.
        @rtype: L{NamedLayer}
        @return: The named layer, attached to this SLD.
        """
        namedlayer = self.get_or_create_element('sld', 'NamedLayer')
        namedlayer.Name = name
        return namedlayer