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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 _maintain_parent(self, request, response):
 """ Maintain the parent ID in the querystring for response_add and response_change. """

        location = response._headers.get("location")
        parent = request.GET.get("parent")
        if parent and location and "?" not in location[1]:
            url = "%s?parent=%s" % (location[1], parent)
            return HttpResponseRedirect(url)
        return response