ubuntu 编译安装 python3.7.5 后 ModuleNotFoundError: No module named

现象：

Traceback (most recent call last):                 
  File "/usr/lib/cnf-update-db", line 8, in <module>
    from CommandNotFound.db.creator import DbCreator
ModuleNotFoundError: No module named 'CommandNotFound'
Reading package lists... Done
E: Problem executing scripts APT::Update::Post-Invoke-Success 'if /usr/bin/test -w /var/lib/command-not-found/ -a -e /usr/lib/cnf-update-db; then /usr/lib/cnf-update-db > /dev/null; fi'
E: Sub-process returned an error code

解决方法：

 vi /usr/lib/cnf-update-db

将#!/usr/bin/python3 替换成#!/usr/bin/python3.6