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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 parse_discovery_service_response(url="", query="", returnIDParam="entityID"):
 """ Deal with the response url from a Discovery Service :param url: the url the user was redirected back to or :param query: just the query part of the URL. :param returnIDParam: This is where the identifier of the IdP is place if it was specified in the query. Default is 'entityID' :return: The IdP identifier or "" if none was given """


        if url:
            part = urlparse(url)
            qsd = parse_qs(part[4])
        elif query:
            qsd = parse_qs(query)
        else:
            qsd = {}

        try:
            return qsd[returnIDParam][0]
        except KeyError:
            return ""