Generate code to "send" a question

tests/mod.rs

@@ -29,8 +29,8 @@ impl TestProtocolServer for DummyServer {
         question.len() as i32
     }
 
-    fn addition(&mut self, arg0: i32, arg1: i32) -> i32 {
-        todo!()
+    fn addition(&mut self, a: i32, b: i32) -> i32 {
+        a + b
     }
 }