presto-main/src/main/java/io/prestosql/operator/aggregation/RealAverageAggregation.java/RealAverageAggregation/RealAverageAggregation
class RealAverageAggregation:    protected RealAverageAggregation()
    {
        super(
                new FunctionMetadata(
                        new Signature(
                                NAME,
                                ImmutableList.of(),
                                ImmutableList.of(),
                                REAL.getTypeSignature(),
                                ImmutableList.of(REAL.getTypeSignature()),
                                false),
                        true,
                        ImmutableList.of(new FunctionArgumentDefinition(false)),
                        false,
                        true,
                        "Returns the average value of the argument",
                        AGGREGATE),
                true,
                false);
    }