installing tensorflow
准备Intel嵌入式邀请赛初选期间，了解学习了tensorflow，下面主要记录tensorflow 2 cpu版本的安装。
Usage
tfrecords
refer to https://zhuanlan.zhihu.com/p/40588218
Estimator
refer to https://www.cnblogs.com/huangyc/p/10341794.html, https://blog.csdn.net/wwangfabei1989/article/details/90516318，https://zhuanlan.zhihu.com/p/76258948.