How can we compare request object in django?

I am building a website in django where user can upload their apk and the app will be modified by server and it return back the modified apk but there i have to limit user to upload 1 apk from 1 category at a time.

     if(request.FILES["app"]):
     name = request.FILES["app"]
    elif(request.FILES["lib"]):
      name = request.FILES["lib"]
    elif.... And more

But i am facing some multivalue dict key error anyone knows any better solution for this please suggest me.