def send_keys(self, text: str = 'cerium') -> None:
        '''Simulates typing keys.'''
        for char in text:
            if '\u4e00' <= char <= '\u9fff':
                raise CharactersException(
                    f'Text cannot contain non-English characters, such as {char!r}.')
        text = re.escape(text)
        self._execute('-s', self.device_sn, 'shell',
                      'input', 'text', text)