code: def on_lstCategories_itemSelectionChanged(self):
          
          self.clear_further_steps()
          # Set widgets
          purpose = self.selected_purpose()
          # Exit if no selection
          if not purpose:
              return
          # Set description label
          self.lblDescribeCategory.setText(purpose["description"])
          self.lblIconCategory.setPixmap(QPixmap(
              resources_path('img', 'wizard', 'keyword-category-%s.svg'
                             % (purpose['key'] or 'notset'))))
          # Enable the next button
          self.parent.pbnNext.setEnabled(True)
docs: Update purpose description label.
  
          .. note:: This is an automatic Qt slot
             executed when the purpose selection changes.