Test MNIST
MNIST数据集 - 知乎 (zhihu.com)
https://zhuanlan.zhihu.com/p/36592188
MNIST handwritten digit database, Yann LeCun, Corinna Cortes and Chris Burges
http://yann.lecun.com/exdb/mnist/
conda create -n mnist
conda activate mnist
conda install tensorflow
conda install jupyterlab
conda install matplotlib