Add comment about 6 params (#6125)

vm/src/function/argument.rs

@@ -55,6 +55,10 @@ into_func_args_from_tuple!((v1, T1), (v2, T2), (v3, T3));
 into_func_args_from_tuple!((v1, T1), (v2, T2), (v3, T3), (v4, T4));
 into_func_args_from_tuple!((v1, T1), (v2, T2), (v3, T3), (v4, T4), (v5, T5));
 into_func_args_from_tuple!((v1, T1), (v2, T2), (v3, T3), (v4, T4), (v5, T5), (v6, T6));
+// We currently allows only 6 unnamed positional arguments.
+// Please use `#[derive(FromArgs)]` and a struct for more complex argument parsing.
+// The number of limitation came from:
+// https://rust-lang.github.io/rust-clippy/master/index.html#too_many_arguments
 
 /// The `FuncArgs` struct is one of the most used structs then creating
 /// a rust function that can be called from python. It holds both positional