There are 4 func A,B,C,D in a class, all the func A,B,C will need to call
the func D in their first line, is there any way simliar to class inhertance
then
I don't need to add func D inside each func and also able to execute it as
below?

Function A()
{
   Function D();
}

Function B()
{
   Function D();
}

Function C()
{
   Function D();
}