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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_slo_url(self):
 """ Gets the SLO URL. :returns: An URL, the SLO endpoint of the IdP :rtype: string """

        url = None
        idp_data = self.__settings.get_idp_data()
        if 'singleLogoutService' in idp_data.keys() and 'url' in idp_data['singleLogoutService']:
            url = idp_data['singleLogoutService']['url']
        return url