Open training and test dataset for machine learning

https://www.quora.com/Where-can-I-find-a-data-set-of-images-to-train-and-test-my-CNN-on-classification-and-object-localization

https://medium.com/playment/top-10-open-image-datasets-for-machine-learning-research-93ab9c18bed1

https://skymind.ai/wiki/open-datasets