def authenticator(): return mock()
def album_catalog(): return mock()
def login(): return mock()
def studio(): return mock(on_project_opened=mock_signal(), on_project_saved=mock_signal())
def listener(): return mock()
def studio(): return mock()
def catalog(): return mock()
def subscriber(): return mock()
def scaler(): return mock()
def mock_signal(): return mock(subscribe=lambda subscriber: None)
def track_catalog(): return mock()
def cheddar(): return mock()
def store(): return mock()