code: @Override
  	public void setup(AbstractInvokable parent) {
  		this.parent = parent;
  
  		@SuppressWarnings("unchecked")
  		final GroupReduceFunction<IN, OUT> combiner =
  			BatchTask.instantiateUserCode(this.config, userCodeClassLoader, GroupReduceFunction.class);
  		this.reducer = combiner;
  		FunctionUtils.setFunctionRuntimeContext(combiner, getUdfRuntimeContext());
  	}
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