all variables are no member variables of the instance 'err' of the class 'test', but they are static variables of the class 'test' itself.
If you would create another instance 'err2 = test()', 'err' and 'err2' would share the same variables workingDir, startDir...
Usually, these variables should be considered to be constants. They are bound to the class itself and not to each instance, therefore
they are not displayed as child of the instance in the workspace widget. If you want to create member variables, you have to create
them in the constructor and prepend a variable 'self.':