title: Does urllib2.urlopen() support no_proxy environment variable?
body: <p><code>urllib.urlopen()</code>'s <a href="https://docs.python.org/2/library/urllib.html#urllib.urlopen" rel="nofollow">docs</a> mentions that the <code>http_proxy</code>/<code>ftp_proxy</code> environment variables can be used to specify a proxy that should be used for the URL opening like this:</p>
  
  <blockquote>
  <pre><code>% http_proxy="http://www.someproxy.com:3128"
  % export http_proxy
  % python
  </code></pre>
  </blockquote>
  
  <p>It also mentions that <code>no_proxy</code> environment variable can be used to prevent using proxy for the specified sites like this:</p>
  
  <pre><code>export no_proxy="cern.ch,ncsa.uiuc.edu,some.host:8080"
  </code></pre>
  
  <p>I use <code>urllib2</code> instead of <code>urllib</code>, but its <a href="https://docs.python.org/2/library/urllib2.html#urllib2.urlopen" rel="nofollow">documentation</a> doesn't explicitly mention the possibility of using <code>no_proxy</code>. Can I use the <code>no_proxy</code> environment variable as well? Will it work as expected?</p>