Get_stream_title() returns last played stream's info

When I call server.core.playback.get_stream_title() from Python (Mopidy version 2.0.0) I get a result even if no stream is playing. It seems like it looks up the last stream that was played. I have a temporary workaround that doesn’t seem very reliable:

server.core.playback.play()
while not server.core.playback.get_stream_title() == None:
    sleep(0.2)
while server.core.playback.get_stream_title() == None:
    sleep(0.2)
print server.core.playback.get_stream_title()    

Any ideas how to solve this better?