How to import a globally installed package to virtualenv folder

What I did after all:

cp -R /usr/lib/python2.7/dist-packages/M2Crypto /home/richard/hello-project/venv/lib/python2.7/site-packages/
cp -R /usr/lib/python2.7/dist-packages/OpenSSL /home/richard/hello-project/venv/lib/python2.7/site-packages/

--system-site-packages

gives access to the global site-packages modules to the virtual environment.

you could do:

$ sudo apt-get install python-m2crypto
$ virtualenv env --system-site-packages

... and you would then have access to m2crypto (along with all other system-wide installed packages) inside your virtualenv.