These entries are queried from radb.net using whois, you can try my project getting these.
:AS-SET-SERVERFIELD as-set: AS-SET-SERVERFIELD descr: Serverfield Co., Ltd. tech-c: SCLA21-AP admin-c: SCLA21-AP mnt-by: MAINT-SCL-TW last-modified: 2024-01-02T04:36:56Z members: AS134094 members: AS138646 source: APNIC