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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 get_cancel_url(self):
 """ Returns the cancel url for this view. if `self.cancel_view` is None the current url will be used. Otherwise the get_view_url will be called with the current bundle using `self.cancel_view` as the view name. """

        if self.cancel_view:
            url = self.bundle.get_view_url(self.cancel_view,
                                            self.request.user, {},
                                            self.kwargs)
        else:
            url = self.request.build_absolute_uri()

        return self.customized_return_url(url)