def update_signing_cert(self, cert_id, status, user_name=None):
        params = {'CertificateId' : cert_id,
                  'Status' : status}
        if user_name:
            params['UserName'] = user_name
        return self.get_response('UpdateSigningCertificate', params)
Change the status of the specified signing certificate from
dataset/ETHPy150Open darcyliu/storyboard/boto/iam/connection.py/IAMConnection.update_signing_cert