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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 set_stream_rates():
    '''set mavlink stream rates'''
    if (not msg_period.trigger() and
        mpstate.status.last_streamrate1 == mpstate.settings.streamrate and
        mpstate.status.last_streamrate2 == mpstate.settings.streamrate2):
        return
    mpstate.status.last_streamrate1 = mpstate.settings.streamrate
    mpstate.status.last_streamrate2 = mpstate.settings.streamrate2
    for master in mpstate.mav_master:
        if master.linknum == 0:
            rate = mpstate.settings.streamrate
        else:
            rate = mpstate.settings.streamrate2
        if rate != -1:
            master.mav.request_data_stream_send(mpstate.settings.target_system, mpstate.settings.target_component,
                                                mavutil.mavlink.MAV_DATA_STREAM_ALL,
                                                rate, 1)