解决Ubuntu Centos下，非root用户、没有权限sudo Permissions，不能更改Python，或者Python缺失库 _bz.so 自定义安装Python

运行mxnet的时候，报错没有bz这个库

File "/usr/local/lib/python3.6.5/lib/python3.6/bz2.py", line 23, in 
    from _bz2 import BZ2Compressor, BZ2Decompressor
ModuleNotFoundError: No module named '_bz2'

网上也有对应的教程
stackoverflow解决办法
https://blog.csdn.net/cuixianpeng/article/details/51926518

由于缺失root权限，我采用自己重新编译Python3代码，并安装到自己当前用户目录下面，就有了随意更改的权限

1.切换到当前用户目录下
cd ~

2.下载Python3.7
wget https://www.python.org/ftp/python/3.7.8/Python-3.7.8.tgz
淘宝镜像：wget https://npm.taobao.org/mirrors/python/3.7.8/Python-3.7.8.tgz

3.解压Python安装包
tar -xzvf Python-3.7.8.tgz

4.编译和安装
cd Python-3.7.8
./configure --prefix=/home/zx/myPython  # 配置安装位置
make
make install

5. 测试是否安装成功
~/myPython/bin/python3.7
结果如下：
Python 3.7.8 (default, Aug  6 2020, 08:56:28) 
[GCC 5.4.0 20160609] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> 

6. 创建venv
~/myPython/bin/python3.7  -m venv myEnv
Ubuntu下启动：
source myEnv/bin/activate
Windows cmd下启动：
myEnv/Scripts/activate.bat
退出：
deactivate

7. 如果缺失什么包，也可以网上下载，拷贝到对应目录
cp /usr/lib/python3.5/lib-dynload/_bz2.cpython-35m-x86_64-linux-gnu.so  /home/zx/myPython/lib/python3.7/lib-dynload

8.重命名
cd ~/myPython/lib/python3.7/lib-dynload
mv _bz2.cpython-35m-x86_64-linux-gnu.so _bz2.cpython-37m-x86_64-linux-gnu.so