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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def is_selected(self, request):
 """ Helper method that returns ``True`` if the menu item is active. A menu item is considered as active if it's URL or one of its descendants URL is equals to the current URL. """

        current_url = request.get_full_path()
        return self.url == current_url or \
            len([c for c in self.children if c.is_selected(request)]) > 0