Hello @skinx.learning
yes that part of the code is not clearly mentioned because of which I was stuck. But also look at the buffer size.
Yes he meant dataset. He was giving me hints of debugging. if that comment is confusing you, refer the below link which mentions each steps clearly.
You can check the debugging step-wise as per instructions given
Your issue is with the point 5.
Let me know if you still have got doubt.
Regards
DP