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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 fullscreen(self):
        ''' Context Manager that enters full-screen mode and restores normal
            mode on exit.

            ::

                with screen.fullscreen():
                    print('Hello, world!')
        '''
        stream = self._stream
        stream.write(self.alt_screen_enable)
        stream.write(str(self.save_title(0)))     # 0 = both icon, title
        stream.flush()
        try:
            yield self
        finally:
            stream.write(self.alt_screen_disable)
            stream.write(str(self.restore_title(0)))  # 0 = icon & title
            stream.flush()