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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 AddATR(self, readernode, atr):
 """Add an ATR to a reader node."""

        capchild = self.AppendItem(readernode, atr)
        self.SetPyData(capchild, None)
        self.SetItemImage(
            capchild, self.cardimageindex, wx.TreeItemIcon_Normal)
        self.SetItemImage(
            capchild, self.cardimageindex, wx.TreeItemIcon_Expanded)
        self.Expand(capchild)
        return capchild