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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 post_async(self, path, params=None):
 """Asynchronously calls a function on a child block Args: path (list):
 The path to post to params (dict):
 parameters for the call Returns: Future: as single Future that will resolve to the result """

        request = Post(self._get_next_id(), path, params)
        request.set_callback(self._q.put)
        future = self._dispatch_request(request)
        return future