'Translate an artifact into a receiver location
:param artifact: The Base64 encoded SAML artifact
:return:'

def artifact2destination(self, artifact, descriptor):

    _art = base64.b64decode(artifact)
    assert (_art[:2] == ARTIFACT_TYPECODE)
    try:
        endpoint_index = str(int(_art[2:4]))
    except ValueError:
        endpoint_index = str(int(hexlify(_art[2:4])))
    entity = self.sourceid[_art[4:24]]
    destination = None
    for desc in entity[('%s_descriptor' % descriptor)]:
        for srv in desc['artifact_resolution_service']:
            if (srv['index'] == endpoint_index):
                destination = srv['location']
                break
    return destination
