Help for assignment 2 in the course "Neural Networks and Deep Learning"

I’m new in these courses and in general in using python.
I have a problem for the assignment 2 of week 2 of the course " Neural Networks and Deep Learning". The exercises seem to me all right and also the results when I run the code but there’is always the object _test that results error and so my grade are low at the end. Can you help me? i write here an example of the result when I run the code:
sigmoid(t_x) = [0.73105858 0.88079708 0.95257413]

NameError Traceback (most recent call last)
2 print("sigmoid(t_x) = " + str(sigmoid(t_x)))
----> 4 sigmoid_test(sigmoid)

NameError: name ‘sigmoid_test’ is not defined

I cannot modify row 4 is a part of code already written.
Please can someone help me and tell me what it’s wrong? how can I define this …_test?
thank you in advance

You filed this question under “AI For Everyone”, but I think you are asking about DLS. I will move the thread for you by using the little “edit pencil” on the title.

That error just means you haven’t run all the previous cells in the notebook. Try “Cell → Run All Above” and then run the test again. Note that you have to do that every time you reopen or restart the notebook. It’s also documented on the DLS FAQ Thread, which is worth a look on general principles.

Thak you very much and sorry for my dummy question.
Thank you also for having moving in the correct category my thread.

I recommend you attend a Python tutorial course, before you proceed too much farther. The courses assume you already have entry-level Python programming skills

Thank you but I didn’t find too hard altough I dedicate not so much time because of my work and the differenti language. However, while I’m attending this course,I’m also reading a good guide of python :blush:.
This community Is very interesting and usefull too, good organization!