def test_getChild(self):
        """
        The C{getChild} method of L{ErrorPage} returns the L{ErrorPage} it is
        called on.
        """
        page = self.errorPage(321, "foo", "bar")
        self.assertIdentical(page.getChild(b"name", object()), page)

        The C{getChild} method of L{ErrorPage} returns the L{ErrorPage} it is
        called on.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_resource.py