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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 DeactivateCard(self, card):
 """Deactivate a card."""

        if hasattr(card, 'connection'):
            card.connection.disconnect()
            if None != self.parent.apdutracerpanel:
                card.connection.deleteObserver(self.parent.apdutracerpanel)
            delattr(card, 'connection')
        self.dialogpanel.OnDeactivateCard(card)