Заменить вот это
for l in vlans.split("\n"):
            match = rx_line.match(l.strip())
            if match:
                r.append({
                    "vlan_id": match.group("vlan_id"),
                    "mac": match.group("mac"),
                    "interfaces": [match.group("interfaces")],
                    "type": {"Dynamic": "D"}[match.group("type")],
                })

На вот это


    for l in vlans.split("\n"):
                match = rx_line.match(l.strip())
                if match:
                    try:
                            r.append({
                                    "vlan_id": match.group("vlan_id"),
                                    "mac": match.group("mac"),
                                    "interfaces": [match.group("interfaces")],
                                    "type": {"Dynamic": "D"}[match.group("type")],
                                    })
                    except KeyError:
                            continue