code: def calendar(self, title="Choose a date", format_str="%Y-%m-%d", date="today", **kwargs):
          
          return self._run_kdialog(title, ["--calendar", title], kwargs)
docs: Show a calendar dialog
  
          Usage: C{dialog.calendar_dialog(title="Choose a date", format="%Y-%m-%d", date="YYYY-MM-DD", **kwargs)}
  
          Note: the format and date parameters are not currently used
  
          @param title: window title for the dialog
          @param format_str: format of date to be returned
          @param date: initial date as YYYY-MM-DD, otherwise today
          @return: a tuple containing the exit code and date
          @rtype: C{DialogData(int, str)}