Traceback (most recent call last):
  File "/usr/share/kde4/apps/system-config-printer-kde/system-config-printer-kde.py", line 1048, in on_btnCleanHeads_clicked
    self.maintenance_command ("Clean all")
  File "/usr/share/kde4/apps/system-config-printer-kde/system-config-printer-kde.py", line 1020, in maintenance_command
    self.lblInfo.set_markup ('<span size="larger">' +
AttributeError: 'GUI' object has no attribute 'lblInfo'