[PyQt] Help on "self"

[David Arnold]

Hi,

I'm not new to Python, but the use of "self" in classes has always been confusing. I working thru Rapid Gui Programming, and I have this code from Chatper 5:

import sys
from PyQt4.QtGui import *

class PenPropertiesDlg(QDialog):
    def __init__(self, parent=None):
        super(PenPropertiesDlg, self).__init__(parent)
        
        widthLabel=QLabel("&Width")
        self.widthSpinBox=QSpinBox()
        

Can someone "gently" explain why the author did not use self.widthLabel=QLabel("&Width").

Thanks.

David.