def get_realtime(self, sid):
"""Identical arguments and return value as trafikanten.get_realtime.
Will call _get_cached_realtime and _cache_realtime to handle caching
properly. Subclasses probably do not need to override this method."""
data = self._get_cached_realtime(sid)
if data == None:
data = trafikanten.get_realtime(sid)
self._cache_realtime(sid, data)
return data
def test_invalid_station_id():
assert trafikanten.get_realtime("does_not_exist") == None
