title: how does "getChild" works in twisted
body: <p>The twisted web documentation says that getChild has to be implemented in that way:</p>
  
  <pre><code>class Hello(Resource):
      isLeaf = True
      def getChild(self, name, request):
          if name == '':
              return self
          return Resource.getChild(self, name, request)$
  </code></pre>
  
  <p>As far as I understand, there is a recursive call to the getChild method
  but who (which method in which class ?) is in charge of removing path
  segments from name ?</p>
  
  <p>Thanks !</p>