Please don’t post your code on the forum. That’s not allowed by the Code of Conduct.
Every time you open a notebook, you have to run all of the cells starting from the top. Typically the first few cells are where the resources are imported and the data set is created.
The other issue is that the grader is telling your code for those functions is not correct.
Hello @hoaianh09012003,
I removed your second attachment while Tom was replying, and please follow Tom’s comments. One more thing that I want you to check is, if you go up the notebook, you should find this code cell that defines x_train, make sure it is there and do as Tom suggested - to run all the cells from top to bottom, then that error you showed in the third attachment should be gone.
Cheers,
Raymond
sorry i don’t know what i should do now can you show me i am very confused
Thank you very much, I’m sorry this is my first time participating so I will learn from experience