Just a renaming as indeed we are dealing with a model.

src/language.ml

@@ -45,17 +45,17 @@ let register_astuple nb_inputs nb_outputs filename env =
 
 let nnet_parser env _ filename _ =
   let open Why3 in
-  let header = Nnet.parse filename in
-  match header with
+  let model = Nnet.parse filename in
+  match model with
   | Error s -> Loc.errorm "%s" s
-  | Ok header -> register_astuple header.n_inputs header.n_outputs filename env
+  | Ok model -> register_astuple model.n_inputs model.n_outputs filename env
 
 let onnx_parser env _ filename _ =
   let open Why3 in
-  let header = Onnx.parse filename in
-  match header with
+  let model = Onnx.parse filename in
+  match model with
   | Error s -> Loc.errorm "%s" s
-  | Ok header -> register_astuple header.n_inputs header.n_outputs filename env
+  | Ok model -> register_astuple model.n_inputs model.n_outputs filename env
 
 let register_nnet_support () =
   Why3.(