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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 onSelectRow(self, event):
 """ Highlight or unhighlight a row for possible deletion. """

        grid = self.grid
        row = event.Row
        default = (255, 255, 255, 255)
        highlight = (191, 216, 216, 255)
        cell_color = grid.GetCellBackgroundColour(row, 0)
        attr = wx.grid.GridCellAttr()
        if cell_color == default:
            attr.SetBackgroundColour(highlight)
            self.selected_rows.add(row)
        else:
            attr.SetBackgroundColour(default)
            try:
                self.selected_rows.remove(row)
            except KeyError:
                pass
        if self.selected_rows and self.deleteRowButton:
            self.deleteRowButton.Enable()
        else:
            self.deleteRowButton.Disable()
        grid.SetRowAttr(row, attr)
        grid.Refresh()