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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 success(self, objects, message=None):
 """Redirects the user to success page with informative message """

        if self.is_context_only(objects):
            return self.redirect(message=_("Changes saved."))

        ids = map(api.get_id, objects)
        if not message:
            message = _("Saved items: {}").format(", ".join(ids))
        return self.redirect(message=message)