Hey @DURGESH_RAO,
I just went over your entire kernel, and couldn’t find any issue. I copied the code for all the first 8 exercises from your kernel and they ran perfectly fine in my Coursera Labs. It looks like you have involuntarily changed something apart from the code that you were supposed to. Can you please try to get a new version of the assignment and run that? You can find the instructions for doing so in this thread. Let me know if this helps.
P.S. - Posting code publicly is against the community guidelines. If a mentor needs to take a look at your code, he/she will ask you to DM it, as I did. So, please make sure that if any solution code is involved, you only DM it to a mentor and not post it publicly.
Cheers,
Elemento