@classmethod
    def register(cls, step_class):
        if not inspect.isclass(step_class):
            raise ValueError('Only classes may be registered.')
        elif not issubclass(step_class, cls._registerable_class):
            raise ValueError('Only %s classes or subclasses may be registered.'
                             % cls._registerable_class.__name__)
        if step_class in cls._cls_registry:
            return False
        else:
            cls._cls_registry.add(step_class)
            return True
Registers a :class:`~horizon.workflows.Step` with the workflow.
dataset/ETHPy150Open Havate/havate-openstack/proto-build/gui/horizon/Horizon_GUI/horizon/workflows/base.py/Workflow.register