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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 on_key_down(self, event):
 """ If user does command v, re-size window in case pasting has changed the content size. """

        keycode = event.GetKeyCode()
        meta_down = event.MetaDown() or event.GetCmdDown()
        if keycode == 86 and meta_down:
            # treat it as if it were a wx.EVT_TEXT_SIZE
            self.do_fit(event)