Update gradio_app.py

gradio_app.py

@@ -87,8 +87,9 @@ def get_parser():
     return parser
 
 def check_auth(username, password):
-    return os.getenv(username) == password
-
+    if os.getenv(username) is not None:
+        return os.getenv(username) == password
+    return False
 if __name__ == "__main__":
     parser = get_parser()
     args = parser.parse_args()