docs: def unregisterWalkthrough(self, walkthrough):
          """
          Unregisters the inputed walkthrough from the application walkthroug
          list.
          
          :param      walkthrough | <XWalkthrough>
          """
          if type(walkthrough) in (str, unicode):
              walkthrough = self.findWalkthrough(walkthrough)
  
          try:
              self._walkthroughs.remove(walkthrough)
          except ValueError:
              pass