code: def form_valid(self, form):
          
  
          self.object = form.save(commit=False)
          self.object.project = self.project
          self.object.save()
  
          # Good to make note of that
          messages.add_message(self.request, messages.SUCCESS, 'Stage %s created' % self.object.name)
  
          return super(ProjectStageCreate, self).form_valid(form)
docs: Set the project on this configuration after it's valid