def removeCallback(self, callback, eventType=None):
        if eventType in None:
            eventType = callback._eventType

        if issubclass(eventType, SelectedTabChangeEvent):
            self.withdrawCallback(SelectedTabChangeEvent, callback)
        else:
            super(TabSheet, self).removeCallback(callback, eventType)
dataset/ETHPy150Open rwl/muntjac/muntjac/ui/tab_sheet.py/TabSheet.removeCallback/operator `is` -> `in`