code: @Override
  	public void setup(AbstractInvokable parent) {
  		@SuppressWarnings("unchecked")
  		final FlatMapFunction<IT, OT> mapper =
  			BatchTask.instantiateUserCode(this.config, userCodeClassLoader, FlatMapFunction.class);
  		this.mapper = mapper;
  		FunctionUtils.setFunctionRuntimeContext(mapper, getUdfRuntimeContext());
  	}
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