Who to get the line number of a field declaration with Javassist?

This is a follow up to: How to get the line number of a method?

I have a java.lang.reflect.Field instance and want to know at which line the declaration was made of in the declaring class.

Currently I have a CtField but it lacks a getLineNumber() method ...

public static int getLineNumberOf(Class<?> type,Field field){
        ClassPool cp = ClassPool.getDefault();
        CtClass ctClass = cp.getCtClass(type.getName());
        CtField ctField = ctClass.getDeclaredField(field.getName());

        ctField.getLineNumber(); 
        //      ^^^^^^^^^^^^^^  that one is missing
}

What is the right way to get the line number?