title: Error running wsgi in python27 and python36
body: <p>I downloaded mod_fcgid-2.3.9 and used it under Apache 2.4.
  I did a 'pip install flup' in python 2.7, and try to run the following code to test wsgi.</p>
  
  <pre><code>from cgi import escape
  import sys, os
  from flup.server.fcgi import WSGIServer
  
  def app(environ, start_response):
      start_response('200 OK', [('Content-Type', 'text/html')])
  
      yield '&lt;h1&gt;FastCGI Environment&lt;/h1&gt;'
  
      yield '&lt;table&gt;'
      for k, v in sorted(environ.items()):
          yield '&lt;tr&gt;&lt;th&gt;%s&lt;/th&gt;&lt;td&gt;%s&lt;/td&gt;&lt;/tr&gt;' % (escape(k), escape(v))
      yield '&lt;/table&gt;'
  
  WSGIServer(app).run()
  </code></pre>
  
  <p>however, the following error encountered</p>
  
  <pre><code>Traceback (most recent call last):
    File "C:\Users\jl\Documents\00-wsgi.py", line 18, in &lt;module&gt; WSGIServer(app).run()
    File "C:\Python27\lib\site-packages\flup\server\fcgi.py", line 112, in run
      sock = self._setupSocket()
    File "C:\Python27\lib\site-packages\flup\server\fcgi_base.py", line 978, in _setupSocket
      sock = socket.fromfd(FCGI_LISTENSOCK_FILENO, socket.AF_INET,
  AttributeError: 'module' object has no attribute 'fromfd'
  </code></pre>
  
  <p>I tried to run the above under python36.
  I did a 'pip install flup6' under python36 environment, then the above program is run and the following error encountered.</p>
  
  <pre><code>Traceback (most recent call last):
    File "C:/Users/jl/Documents/00-wsgi36.py", line 20, in &lt;module&gt;
      WSGIServer(app).run()
    File "C:\Python36\lib\site-packages\flup\server\fcgi.py", line 112, in run
      sock = self._setupSocket()
    File "C:\Python36\lib\site-packages\flup\server\fcgi_base.py", line 988, in _setupSocket
      socket.SOCK_STREAM)
    File "C:\Python36\lib\socket.py", line 460, in fromfd
      nfd = dup(fd)
  OSError: [WinError 10038] An operation was attempted on something that is not a socket
  </code></pre>
  
  <p>What should I do to solve the problems in both python27 and python36 environment?</p>