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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 rotation(self):
 """ Rotaion of the phone 0: normal 1: home key on the right 2: home key on the top 3: home key on the left """

        if self.screen_rotation in range(4):
            return self.screen_rotation
        return self.adb_device.rotation() or self.info['displayRotation']