Extra brackets in Publisher API sample

[vivialearn]

I got a 400 error when running code based on this line:

https://github.com/googlesamples/android-play-publisher-api/blob/f4e9a7609f1528ac82fced693e0bff2939ce2931/v3/python/upload_apks_rollout.py#L67

The error was:

"Invalid value at 'track_config.releases[0].version_codes[0]' (TYPE_INT64), "[5]"".
Details: "[{'@type': 'type.googleapis.com/google.rpc.BadRequest', 'fieldViolations': [{'field': 'track_config.releases[0].version_codes[0]', 'description': 'Invalid value at \'track_config.releases[0].version_codes[0]\' (TYPE_INT64), "[5]"'}]}]"

When I removed the inner brackets, the error disappeared:

u'versionCodes': [str(apk_response['versionCode'])]