https://www.kaggle.com/c/quickdraw-doodle-recognition/discussion/70912#417458
https://www.kaggle.com/c/quickdraw-doodle-recognition/discussion/70762
https://www.kaggle.com/c/quickdraw-doodle-recognition/discussion/70558
https://www.kaggle.com/c/quickdraw-doodle-recognition/discussion/70307