Exercise 2 of week_2

Exercise 2 is to calculate the determinant of a matrix A and to solve a system of linear equatios. My code is.
solution code removed - moderation

IT RUN OK, according to solution. More over they say all test passed
BUT IN THE GRADING put :
Failed test case: Determinant d has incorrect type…
Expected:
<class ‘float’>,
but got:
<class ‘NoneType’>
I check the type of variable d and the type is float.
Why, the grading says the type is NoneType

Hi, thanks for your post!

I have removed your solution, because posting solution to codes and quizzes goes against our community.

Can you please be sure that you have removed any #grade-up-to-here before this question? If you left one after exercise 1, this will prevent your code from being graded apart from the first time it encounters “#grade-up-to-here

Thanks,
Lucas

This code was not a solution because was graded with a zero- The question is:
exercise is graded with zero, because it says that variable type is NonTipe.
I defined the type as float to avoid this. But the grading continous with the same answer.
The same happend with different exercises.
In my computer i installed pytho 3 and works. Why works also in my book when Run, but is graded as zero. If problem is not the coding, because ti runs and give a correct solution, Why grade is zero. I cannot finish the course due to this problem,

Can you send my your notebook so I can have a look at it? Please send me privately.