What you are doing here:
```log_resp = "[" + logIn_resp[idx:idx2] + "]"```
is creating a json array whose only element is the content ```logIn_resp[idx:idx2]```. Unless ```logIn_resp[idx:idx2]``` is a scalar, it should be valid json by itself. That means you should be able to call ```json.loads(logIn_resp[idx:idx2])```