def _registerPrimitive(self, objectId, primitive):
        self._objectRegistry.definePrimitive(
            objectId,
            primitive
            )
`_registerPrimitive`: register a primitive (defined by `isPrimitive`)
dataset/ETHPy150Open ufora/ufora/packages/python/pyfora/PyObjectWalker.py/PyObjectWalker._registerPrimitive