instantiation always throws "Service Unavailable"

[michael-ts]

findi = FindMyIPhone(username,password)
Traceback (most recent call last):
File "", line 1, in
File "findi.py", line 17, in init
self.get_partition()
File "findi.py", line 34, in get_partition
headers, content = self.post('/fmipservice/device/%s/initClient' % self.username, body, None, True)
File "findi.py", line 260, in post
resp = opener.open(req)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/urllib2.py", line 400, in open
response = meth(req, response)
File "findi.py", line 292, in http_response
'http', request, response, code, msg, hdrs)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/urllib2.py", line 438, in error
return self._call_chain(_args)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/urllib2.py", line 372, in _call_chain
result = func(_args)
File "/System/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/urllib2.py", line 521, in http_error_default
raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
urllib2.HTTPError: HTTP Error 503: Service Unavailable

Service is up and available when viewed from (e.g.) https://icloud.com/#find