Hello, I have a few questions that I would need to understand better

[TK997]

First, let me thank you for your deep-tutorials about ML, I really think it helped a lot of people to get a better understanding.
Secondly, if we take a look at this: https://github.com/hunkim/PyTorchZeroToAll/blob/master/01_basics.py
is the purpose of that code, just to setup everything as you show in youtube video? If I understand correctly, w is just to help us "walk-over" some field of different numbers right?
Well my confusion raises from not being capable of understanding why we get such graph and why w at 2 should have 0 loss :/
Hopefully you can understand where my issue is :)

Best of regards,
TK