Update app.py

app.py

@@ -42,7 +42,7 @@ def api():
                     users.append("others")
                 print(users)
 
-                matrix = [[0 for _ in range(users)] for _ in range(users)]
+                matrix = [[0 for _ in range(len(users))] for _ in range(len(users))]
                 print(matrix)
 
                 for msg_id in message_list: