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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):
 """ Saves the current terminal attributes and makes the tty raw. This method returns None immediately. """


        if os.isatty(self.fd.fileno()) and self.israw():
            self.original_attributes = termios.tcgetattr(self.fd)
            tty.setraw(self.fd)