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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 start(self):
 """ Start trapping WINCH signals and resizing the PTY. This method saves the previous WINCH handler so it can be restored on `stop()`. """


        def handle(signum, frame):
            if signum == signal.SIGWINCH:
                self.pty.resize()

        self.original_handler = signal.signal(signal.SIGWINCH, handle)