move generated stubs to separate directory, too messty

django-stubs-generated/contrib/messages/views.pyi

@@ -0,0 +1,10 @@
+from typing import Any, Dict, Optional
+
+from django.forms.forms import Form
+from django.http.response import HttpResponseRedirect
+
+
+class SuccessMessageMixin:
+    success_message: str = ...
+    def form_valid(self, form: Form) -> HttpResponseRedirect: ...
+    def get_success_message(self, cleaned_data: Dict[str, str]) -> str: ...