title: ModuleNotFoundError when using python venv even though pip freeze shows the packages are installed
body: <p>I am new to venv and virtual environments for Python in general. I created an environment called .venv using:</p>
  
  <pre><code>python3 -m venv .venv
  </code></pre>
  
  <p>I then activated it and installed some packages. When I list the packages using <code>pip freeze</code>, I get the following:</p>
  
  <pre><code>(.venv) $ pip freeze
  boto==2.48.0
  bz2file==0.98
  certifi==2017.7.27.1
  chardet==3.0.4
  click==6.7
  ...
  </code></pre>
  
  <p>However, if I try to import any of these packages, I get a <code>ModuleNotFoundError</code>, e.g.:</p>
  
  <pre><code>(.venv) $ python -c 
  "import click"
  Traceback (most recent call last):
    File "&lt;string&gt;", line 1, in &lt;module&gt;
  ModuleNotFoundError: No module named 'click'
  </code></pre>
  
  <p>What am I missing???</p>