ubuntu安装python3.7，并更新python默认指向为python3.7

ubuntu安装python3.7，并更新python默认指向为python3.7

https://blog.csdn.net/u014775723/article/details/85213793?utm_medium=distribute.pc_relevant_t0.none-task-blog-BlogCommendFromMachineLearnPai2-1.add_param_isCf&depth_1-utm_source=distribute.pc_relevant_t0.none-task-blog-BlogCommendFromMachineLearnPai2-1.add_param_isCf