title: Install and using pip and virtualenv in Docker
body: <p>I want to install Python, Pip and virtualenv in a Docker container which is Ubuntu, I create the image through Dockerfile:</p>
  
  <pre><code>FROM ubuntu:16.04
  
  RUN apt-get update -y
  
  RUN apt-get
  
  RUN apt-get python3 -y
  
  RUN apt-get install python3-pip -y
  
  RUN pip install virtualenv
  ...
  </code></pre>
  
  <p>When it went here, it came out "/bin/sh: 1: pip: not found", but there's no exception showed in the installation process, is this mean I didn't install pip right? Or should I do anything else before I use pip order? </p>
  
  <p>Then I changed the Dockerfile like this:</p>
  
  <pre><code>...
  RUN apt-get python3 -y
  
  RUN apt-get install python3-pip -y
  
  RUN apt-get install python3-virtualenv -y 
  
  RUN virtualenv --no-stie-packages -p /path/python3 py3env
  ...
  </code></pre>
  
  <p>but it still saying /bin/sh: 1: virtualenv: not found, <a href="https://i.stack.imgur.com/pNS43.png" rel="noreferrer">here is it</a></p>
  
  <p>I also installed git, git clone order ran correctly, can be used. Where am I wrong, or how should I do?</p>