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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 js_query(self, query: str) -> Awaitable: """Send query to related DOM on browser. :param str query: single string which indicates query type. """

        if self.connected:
            self.js_exec(query, self.__reqid)
            fut = Future()  # type: Future[str]
            self.__tasks[self.__reqid] = fut
            self.__reqid += 1
            return fut
        f = Future()  # type: Future[None]
        f.set_result(None)
        return f