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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 OnLineWidth(self, event):
 """Line width choice event handler"""


        linewidth_combobox = event.GetEventObject()
        idx = event.GetInt()
        width = int(linewidth_combobox.GetString(idx))
        borders = self.bordermap[self.borderstate]

        post_command_event(self, self.BorderWidthMsg, width=width,
                           borders=borders)