1. Install wsgi apache module
apt-get install libapache2-mod-wsgi
a2enmod wsgi
2. Download wsgi template
cd /usr/local/vesta/data/templates/web
wget http://c.vestacp.com/0.9.8/ubuntu/wsgi/apache2.tar.gz
tar -xzvf apache2.tar.gz
rm -f apache2.tar.gz
3. Create new package or set wsgi as apache template in the existing package
4. Add new user and assing him package with wsgi template
5. Add new domain and check the result