well different approach, do a snmpwalk and look if you can find the OID in the below function.
check_info[“fortigate_cpu”] = {
“check_function” : check_fortigate_cpu,
“inventory_function” : lambda info: [(None, “fortigate_cpu_default_levels”)],
“service_description” : “CPU utilization”,
“has_perfdata” : True,
“group” : “cpu_utilization”,
“snmp_scan_function” : lambda oid: oid(“.1.3.6.1.4.1.12356.1.8.0”),
“snmp_info” : ( “.1.3.6.1.4.1.12356.1”, [ 8 ]),
}