I accidentally deleted the cell testing function related to the def pdf_binomial(x, n, p) and there is no way to retrieve it: re-starting cells, rebooting servers, etc… do not work. Very inconvenient design. Please use Read-Only cell for testing purposes.
Anyone can copy and paste this cell here? The testing cell right below def pdf_gaussian(x, mu, sigma):
Have a look in the first optional reading of the assignment.
Go to refreshing procedure and follow the instructions. It happened to me once and there weren’t any instructions to recover the original file. Nowadays, most courses which work with Jupyter Notebooks provide these instructions to help us.