def test_lookupProcedure(self):
        """
        A subclass of L{XMLRPC} can override C{lookupProcedure} to find
        procedures that are not defined using a C{xmlrpc_}-prefixed method name.
        """
        self.createServer(TestLookupProcedure())
        what = "hello"
        d = self.proxy.callRemote("echo", what)
        d.addCallback(self.assertEqual, what)
        return d

        A subclass of L{XMLRPC} can override C{lookupProcedure} to find
        procedures that are not defined using a C{xmlrpc_}-prefixed method name.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_xmlrpc.py