Currently, the implementation of SimpleTransformationTranslator restricts that OPERATOR and PYTHON use case could not be used in the same operator. For batch mode of Python DataStream API:
- OPERATOR use case will be added firstly in BatchExecutionUtils.applyBatchExecutionSettings for a keyed operator during translation
- Then the PYTHON use case which is set in the transformation could not be added in SimpleTransformationTranslator as the streamNode.getManagedMemoryOperatorScopeUseCaseWeights() is not empty.
We need to remove the restriction in SimpleTransformationTranslator if there are no special reasons.