presto-main/src/main/java/io/prestosql/operator/window/ReflectionWindowFunctionSupplier.java/ReflectionWindowFunctionSupplier/getDescription
class ReflectionWindowFunctionSupplier:    private static String getDescription(AnnotatedElement annotatedElement)
    {
        Description description = annotatedElement.getAnnotation(Description.class);
        return (description == null) ? null : description.value();
    }