title: How to change the url using django process_request .
body: <p>This is my code :</p>
  
  <pre><code>class MobileMiddleware(object):
  
      def process_request(self, request):
          if request.path.startswith('/core/mypage/'):
              request.path='/core/mypage/?key=value'
              print request.path,'aaaa'
  </code></pre>
  
  <p>I want to add a param <code>key</code> when the page url is <code>/core/mypage/</code>,</p>
  
  <p>and the url of the web browser would be changed to <code>http:www.ss.com/core/mypage/?key=value</code></p>
  
  <p>However,  the url in the browser is not changed.</p>
  
  <p>What can I do?</p>