'When called with the name of a defined render method,
L{Element.lookupRenderMethod} returns that render method.'

def test_definedRenderer(self):

    class ElementWithRenderMethod(Element, ):
        @renderer
        def foo(self, request, tag):
            return 'bar'
    foo = ElementWithRenderMethod().lookupRenderMethod('foo')
    self.assertEqual(foo(None, None), 'bar')
