virtualenv with python 2.7 code example

Example 1: python virtual environment

python3 -m venv env
python -m virtualenv env #py2

source env/bin/activate

#all this is on same directory

Example 2: start virtualenv

source env/bin/activate

Example 3: virtualenv python2

virtualenv --python=/usr/bin/python2.6 <path/to/new/virtualenv/>

Example 4: virtual env python 2

virtualenv -p C:\Python27\python.exe venv
.\venv\Scripts\activate