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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 _send_register_payload(self, websocket):
 """Send the register payload."""

        file = os.path.join(os.path.dirname(__file__), HANDSHAKE_FILE_NAME)

        data = codecs.open(file, 'r', 'utf-8')
        raw_handshake = data.read()

        handshake = json.loads(raw_handshake)
        handshake['payload']['client-key'] = self.client_key

        yield from websocket.send(json.dumps(handshake))
        raw_response = yield from websocket.recv()
        response = json.loads(raw_response)

        if response['type'] == 'response' and \
                        response['payload']['pairingType'] == 'PROMPT':
            raw_response = yield from websocket.recv()
            response = json.loads(raw_response)
            if response['type'] == 'registered':
                self.client_key = response['payload']['client-key']
                self.save_key_file()