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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 encode_send_message(payload, rq_sa, rs_sa, channel, seq, tracking=1):
 """Encode a send message command and embedd the message to be send. payload: the message to be send as bytestring rq_sa: the requester source address rs_sa: the responder source address channel: the channel seq: the sequence number tracking: tracking Returns an encode send message as bytestring """

    req = create_request_by_name('SendMessage')
    req.channel.number = channel
    req.channel.tracking = tracking
    data = encode_message(req)

    header = IpmbHeaderReq()
    header.netfn = req.__netfn__
    header.rs_lun = 0
    header.rs_sa = rs_sa
    header.rq_seq = seq
    header.rq_lun = 0
    header.rq_sa = rq_sa
    header.cmd_id = req.__cmdid__

    return encode_ipmb_msg(header, data + payload)