title: ImportError: No module named 'bs4' with virtualenv python3
body: <p>I know this is a common issue but I still can't figure how to make it work.
  I'm trying to use bs4 inside a virtual environment but I have this error <code>ImportError: No module named 'bs4'</code></p>
  
  <p>I have my virtualenv activated :</p>
  
  <pre><code>pip install bs4
  Requirement already satisfied: bs4 in /home/****/.virtualenvs/****/lib/python3.5/dist-packages
  Requirement already satisfied: beautifulsoup4 in /home/****/.virtualenvs/****/lib/python3.5/dist-packages (from bs4)
  </code></pre>
  
  <p>My scripts start with </p>
  
  <pre><code>!/usr/bin/python3.5 
  # -*-coding:Utf-8 -*
  import json
  import hashlib
  from bs4 import BeautifulSoup
  </code></pre>
  
  <p>Any help is welcome !</p>