def unregister(self, class_):
        manager = manager_of_class(class_)
        manager.unregister()
        manager.dispose()
        self.dispatch.class_uninstrument(class_)
        if ClassManager.MANAGER_ATTR in class_.__dict__:
            delattr(class_, ClassManager.MANAGER_ATTR)

# this attribute is replaced by sqlalchemy.ext.instrumentation
# when importred.
dataset/ETHPy150Open RoseOu/flasky/venv/lib/python2.7/site-packages/sqlalchemy/orm/instrumentation.py/InstrumentationFactory.unregister/original