presto-main/src/main/java/io/prestosql/operator/scalar/FormatFunction.java/FormatFunction/FormatFunction
class FormatFunction:    private FormatFunction()
    {
        super(new FunctionMetadata(
                Signature.builder()
                        .name(NAME)
                        .typeVariableConstraints(withVariadicBound("T", "row"))
                        .argumentTypes(VARCHAR.getTypeSignature(), new TypeSignature("T"))
                        .returnType(VARCHAR.getTypeSignature())
                        .build(),
                false,
                ImmutableList.of(new FunctionArgumentDefinition(false), new FunctionArgumentDefinition(false)),
                true,
                true,
                "formats the input arguments using a format string",
                SCALAR));
    }