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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def toggle_check_all_eventtype(self):
 """Check 'All' if all event types are checked in event type scroll."""

        checklist = asarray([btn.isChecked for btn in self.idx_eventtype_list])
        
        if not checklist.all():
            self.check_all_eventtype.setChecked(False)