问题
I use python virtual environments regularly and generally execute the standard method of installing any necessary site packages after running installing the virtual environment. However, when I don't want to use all of the original environment's site-packages then in order to install a number of additional packages to the new environment I find the process tedious, especially when non pypi pacakges are required for my work. I haven't managed to find a means of moving a global site package into an existing virtual environment. The work flow for this is as follows
I'd like to be able to first create a virtual environment from a full python installation, without using the --system-site-packagesoption. Then, I'd like to be able to selectively move site-pacakges over to the new virtual environment.
This is, of course, something that I can get by without, but it would be a convenience if it is possible.
来源：https://stackoverflow.com/questions/29885524/how-can-i-move-global-packages-into-a-virtual-environment-after-creating-a-virtu