Ubuntu 20.04 支持 Python 3.6 和 Python 3.8。命令python3 -m venv my_venv使用 python 3.8 创建虚拟环境，它按预期工作。
然而，尝试python3.6 -m venv my_venv3.6是行不通的。我得到的回应是/usr/bin/python3.6: No module named venv。
我尝试使用virtualenv --python=/usr/bin/python3.6 my_venv3.6，结果是：
RuntimeError: failed to query /usr/bin/python3.6 with code 1 err: ...
我还尝试安装sudo apt install python3.6-venv导致：
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package python3.6-venv is not available, but is referred to by another package.
This may mean that the package is missing, …