The function “L_model_forward(X, parameters)” is central to the code but I can’t get it correct in any way!! Almost probably my problem is with: "Don’t forget to keep track of the caches in the “caches” list. To add a new value c to a list , you can use list.append(c)"
I am not forgetting to “keep track of the caches”! I just don’t know how to do it!! 
Any help will be appreciated.
They just told you, right? 
I’m not supposed to actually write the code for you, but here’s another way to translate what they said in the instructions:
Suppose I have a list called myList and I want to add a new element called newElement to it. The code would be:
myList.append(newElement)
Note that there is no “assignment” statement involved there: this is “object oriented” programming. You are invoking the “append()” method on the object (list) in question.
So, I just replace “myList” and “newElement” by what is in the code 
. That’s a clever way to help someone with a code without giving him the exact code 
.
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