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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 OnDirectionChoice(self, event):
 """Direction choice event handler"""


        label = self.direction_choicectrl.GetItems()[event.GetSelection()]
        param = self.choice_label2param[label]
        self.attrs["direction"] = param

        post_command_event(self, self.DrawChartMsg)