upload autograd

Author: L1aoXingyu

README.md

@@ -18,7 +18,7 @@ Learn Deep Learning with PyTorch
 ### part1: 深度学习基础
 - Chapter 2: PyTorch基础
     - [Tensor和Variable](https://github.com/SherlockLiao/code-of-learn-deep-learning-with-pytorch/blob/master/chapter2_PyTorch-Basics/Tensor-and-Variable.ipynb)
-    - 自动求导机制
+    - [自动求导机制](https://github.com/SherlockLiao/code-of-learn-deep-learning-with-pytorch/blob/master/chapter2_PyTorch-Basics/autograd.ipynb)
     - 数据的读取
     - autograd.function的介绍
     - Module和Sequential