Volodymyr

I had the same difference problem between gradients when running locally, because I used GPU to store tensors and perform computations. Once I changed to CPU, I had the difference...

Also some of the data is missing. For example `data_w3_ex1.csv` from week 3 optional lab 1 and images for the notebook `C2W3_Lab_01_Model_Evaluation_and_Selection.ipynb`.

I get the same error when doing `BUILD_EXTENSIONS=True make install`. It also says ```error: linking with `cc` failed: exit status: 1``` for me. My gcc is 10.3 and openssl is...