Protected Access Modifier - Variables, methods and constructors which are declared protected in a superclass can be accessed only by the subclasses in other package or any class within the package of the protected members' class.

Java access to protected member in subclass in different package, using object reference of parent type
here is a part of my code :

class projet(object):

    def nameCouche(self):

        valLissage = float(ui.valLissage.displayText())    
        return (valLissage)         
    valCouche = nameCouche() # asks for a positional argument but 'self' doesnt work   

    def choixTraitement(self):
        ui.okLissage.clicked.connect(p.goLissage)

    def goLissage(self, valCouche):
        if ui.chkboxLissage.isChecked():
            print(valCouche) # result is False
            os.system(r'"C:\Program Files\FME\fme.exe" D:\Stelios\..... --MAX_NUM_POINTS {0}'.format(valCouche))


So I would like to use valCouche in goLissage method but it doesnt work.
I thought that valCouche would have the argument of valLissage but instead it gives False as a value.
I've tried different alternatives but still doesnt work.
