Hi OliveraN,
The comment for the outermost loop states:
# loop over the batch of training examples
Which variable should you use here?
The comment for the second loop states:
# loop over vertical axis of the output volume
You calculated the dimensions of the CONV output volume earlier using the given formula. Which variable indicates the vertical axis dimension?
The comment for the third loop states:
# loop over horizontal axis of the output volume
Which variable indicates the horizontal axis dimension?
The comment for the innermost loop states:
# loop over channels (= #filters) of the output volume
Which variable indicates the number of channels of the output volume?
Also, think about how to use the stride on the input volume in selecting a slice from it.
Good luck!