Update __init__.py

allgo/__init__.py

@@ -47,7 +47,7 @@ class Init:
         string
             allgo login page link or already initialized message
         """
-        if API_token is None
+        if not API_token_valid:
             API_token = get_random_string(length=32)
             msg = "allgo_token = " + API_token
             msg += "<p>Sign in with your existing <a href=\"https://allgo18.inria.fr/accounts/login/?token=" + API_token+  "\">A||GO account </a></p>"