This grabs the event tags from the dn designator. They look like this:
    uni/tn-DataDog/ap-DtDg-AP1-EcommerceApp/epg-DtDg-Ecomm/HDl2IngrPktsAg1h

def get_event_tags_from_dn(dn):
    """
    This grabs the event tags from the dn designator. They look like this:
    uni/tn-DataDog/ap-DtDg-AP1-EcommerceApp/epg-DtDg-Ecomm/HDl2IngrPktsAg1h
    """
    tags = []
    node = get_node_from_dn(dn)
    if node:
        tags.append("node:" + node)
    app = get_app_from_dn(dn)
    if app:
        tags.append("app:" + app)
    bd = get_bd_from_dn(dn)
    if bd:
        tags.append("bd:" + bd)
    cep = get_cep_from_dn(dn)
    if cep:
        tags.append("mac:" + cep)
    ip = get_ip_from_dn(dn)
    if ip:
        tags.append("ip:" + ip)
    epg = get_epg_from_dn(dn)
    if epg:
        tags.append("epg:" + epg)
    return tags