how do i make use of seticon inherited by QCheckBox to display icon with exclusive checkboxes

i found a link here but doesnt have any example how to do so
http://riverbankcomputing.co.uk/static/Docs/PyQt4/html/qabstractbutton.html#setIcon

So I figured out how to display icons , now I need to know how can i make them exclusive

          self.mayachkBox=QtGui.QCheckBox()
          mayaIcon=QtGui.QPixmap("images/Maya_Icon.png")
          self.mayachkBox.setIcon(QtGui.QIcon(mayaIcon))
          self.nukechkBox=QtGui.QCheckBox()
          nukeIcon= QtGui.QPixmap("images/nuke_icon.png")
          self.nukechkBox.setIcon(QtGui.QIcon(nukeIcon))
          chkboxLayout=QtGui.QHBoxLayout()
          chkboxLayout.addWidget(self.mayachkBox)
          chkboxLayout.addWidget(self.nukechkBox)

any help or suggestion will be appreciated!!!