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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(self, destination, body, content_type=None, headers=None, **keyword_headers):
 """ Send a message to a destination. :param str destination: the destination of the message (e.g. queue or topic name) :param body: the content of the message :param str content_type: the content type of the message :param dict headers: a map of any additional headers the broker requires :param keyword_headers: any additional headers the broker requires """

        assert destination is not None, "'destination' is required"
        assert body is not None, "'body' is required"
        headers = utils.merge_headers([headers, keyword_headers])
        headers[HDR_DESTINATION] = destination
        if content_type:
            headers[HDR_CONTENT_TYPE] = content_type
        if self.auto_content_length and body and HDR_CONTENT_LENGTH not in headers:
            headers[HDR_CONTENT_LENGTH] = len(body)
        self.send_frame(CMD_SEND, headers, body)