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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 OnAddCards(self, addedcards):
 """Called when a card is inserted. Adds a smart card to the smartcards tree."""

        parentnode = self.root
        for cardtoadd in addedcards:
            childCard = self.AppendItem(parentnode, toHexString(cardtoadd.atr))
            self.SetItemText(childCard, toHexString(cardtoadd.atr))
            self.SetPyData(childCard, cardtoadd)
            self.SetItemImage(
                childCard, self.cardimageindex, wx.TreeItemIcon_Normal)
            self.SetItemImage(
                childCard, self.cardimageindex, wx.TreeItemIcon_Expanded)
            self.Expand(childCard)
        self.Expand(self.root)
        self.EnsureVisible(self.root)
        self.Repaint()