def _set_sa_auth_only(self, v, load=False):
    """
    Setter method for sa_auth_only, mapped from YANG variable /macsec/interfaces/interface/scsa_tx/scsa_tx/state/counters/sa_auth_only (oc-yang:counter64)
    If this variable is read-only (config: false) in the
    source YANG file, then _set_sa_auth_only is considered as a private
    method. Backends looking to populate this variable should
    do so via calling thisObj._set_sa_auth_only() directly.

    YANG Description: Secure Association Authenticated only TX Packets counter.