python 3 install python2 venv code example
Example 1: virtualenv python2
virtualenv --python=/usr/bin/python2.6 <path/to/new/virtualenv/>
Example 2: pip3 venv install
python3 -m venv /path/to/new/virtual/environment
source <venv>/bin/activate
virtualenv --python=/usr/bin/python2.6 <path/to/new/virtualenv/>
python3 -m venv /path/to/new/virtual/environment
source <venv>/bin/activate