_x = functools.partial(xpath_with_ns, ns_map={
'ttml': 'http://www.w3.org/ns/ttml',
'ttaf1': 'http://www.w3.org/2006/10/ttaf1',
_x = functools.partial(xpath_with_ns, ns_map={
'ttml': 'http://www.w3.org/ns/ttml',
'ttaf1': 'http://www.w3.org/2006/10/ttaf1',