Course 4 Week 4 Assignment 2 train_step (UNQ_C5)

Right, so the question is where is a_G generated? Maybe start by printing the type of it right after the call to vgg_model_outputs. What does that show? Is it wrong on the first iteration or on some subsequent iteration? Then work your way backwards one step at a time. Are you sure you didn’t modify any of the cells that aren’t graded? You can also compare to a clean notebook to make sure (see the FAQ Thread topic on that).