Two functions, ``service()`` and ``shared_service()`` make somebody think that service class returns new instance typically. At first, it was right.
It is turned over by github issue #55. Now, Service class returns shared instance by default.
I think ``service()`` should return shared instance, but I cannot judge whether we should do or not do from now.
It is turned over by github issue #55. Now, Service class returns shared instance by default.
I think ``service()`` should return shared instance, but I cannot judge whether we should do or not do from now.