no more errors for invalid tokens

shiftregister/app/middleware.py

@@ -10,7 +10,7 @@ def check_helper(get_response):
         # Code to be executed for each request before
         # the view (and later middleware) are called.
         if request.session.get("token"):
-            tk = LoginToken.objects.get(pk=request.session.get("token"))
+            tk = LoginToken.objects.filter(pk=request.session.get("token")).first()
             if not tk:
                 del request.session["token"]
             else: