autograd

 https://www.youtube.com/watch?v=IKS3Lee_Vmo

https://www.youtube.com/watch?v=IHZwWFHWa-w&t=912s

https://www.youtube.com/watch?v=Ilg3gGewQ5U&t=290s

https://www.youtube.com/watch?v=MswxJw-8PvE&t=696s

PyTorch Autograd Explained - In-depth Tutorial

https://www.youtube.com/watch?v=9aBpF0-JH7A

https://www.youtube.com/watch?v=wG_nF1awSSY

https://www.youtube.com/watch?v=WsQQvHm4lSw