https://github.com/https-deeplearning-ai/tensorflow-1-public/blob/main/C4/W4/ungraded_labs/C4_W4_Lab_2_Sunspots.ipynb
https://github.com/https-deeplearning-ai/tensorflow-1-public/blob/main/C4/W4/ungraded_labs/C4_W4_Lab_3_DNN_only.ipynb