Install virtual env in linux

 https://gist.github.com/Geoyi/d9fab4f609e9f75941946be45000632b

# How to install virtualenv:

### Install **pip** first

    sudo apt-get install python3-pip

### Then install **virtualenv** using pip3

    sudo pip3 install virtualenv 

### Now create a virtual environment 

    virtualenv venv 

>you can use any name insted of **venv**

### You can also use a Python interpreter of your choice

    virtualenv -p /usr/bin/python2.7 venv
  
### Active your virtual environment:    
    
    source venv/bin/activate
    
### Using fish shell:    
    
    source venv/bin/activate.fish

### To deactivate:

    deactivate

### Create virtualenv using Python3
    virtualenv -p python3 myenv

### Instead of using virtualenv you can use this command in Python3
    python3 -m venv myenv