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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 start_response(self, stream_id, headers, *, end_stream=False):
 """ Start a response by sending given headers on the given stream. This may block until the underlying transport becomes writable. :param stream_id: Which stream to send response on. :param headers: A list of key-value tuples as headers. :param end_stream: To send a response without body, set `end_stream` to `True` (default `False`). """

        yield from self._resumed.wait()
        self._conn.send_headers(stream_id, headers, end_stream=end_stream)
        self._flush()