These entries are queried from radb.net using whois, you can try my project getting these.
:AS136450 route: 103.88.140.0/22 descr: Kastech Computer Valley origin: AS136450 mnt-by: MAINT-KASTECH-BD country: BD mnt-routes: MAINT-KASTECH-BD mnt-lower: MAINT-KASTECH-BD last-modified: 2017-03-22T10:59:33Z source: APNIC rpki-ov-state: valid route: 103.88.140.0/23 descr: Kastech Computer Valley origin: AS136450 mnt-by: MAINT-KASTECH-BD country: BD mnt-routes: MAINT-KASTECH-BD mnt-lower: MAINT-KASTECH-BD last-modified: 2017-03-22T10:59:40Z source: APNIC rpki-ov-state: valid route: 103.88.140.0/24 descr: Kastech Computer Valley origin: AS136450 mnt-by: MAINT-KASTECH-BD country: BD mnt-routes: MAINT-KASTECH-BD mnt-lower: MAINT-KASTECH-BD last-modified: 2017-03-22T10:59:46Z source: APNIC rpki-ov-state: valid route: 103.88.141.0/24 descr: Kastech Computer Valley origin: AS136450 mnt-by: MAINT-KASTECH-BD country: BD mnt-routes: MAINT-KASTECH-BD mnt-lower: MAINT-KASTECH-BD last-modified: 2017-03-22T11:00:24Z source: APNIC rpki-ov-state: valid route: 103.88.142.0/23 descr: Kastech Computer Valley origin: AS136450 mnt-by: MAINT-KASTECH-BD country: BD mnt-routes: MAINT-KASTECH-BD mnt-lower: MAINT-KASTECH-BD last-modified: 2017-03-22T11:00:37Z source: APNIC rpki-ov-state: valid route: 103.88.142.0/24 descr: Kastech Computer Valley origin: AS136450 mnt-by: MAINT-KASTECH-BD country: BD mnt-routes: MAINT-KASTECH-BD mnt-lower: MAINT-KASTECH-BD last-modified: 2017-03-22T11:00:31Z source: APNIC rpki-ov-state: valid route: 103.88.143.0/24 descr: Kastech Computer Valley origin: AS136450 mnt-by: MAINT-KASTECH-BD country: BD mnt-routes: MAINT-KASTECH-BD mnt-lower: MAINT-KASTECH-BD last-modified: 2017-03-22T11:00:49Z source: APNIC rpki-ov-state: valid route: 116.204.230.0/24 origin: AS136450 descr: Md. Zakir Hossain House: 146, Road: 02, Block: A, Mirpur-12, mnt-by: MAINT-KASTECH-BD last-modified: 2020-11-19T06:49:48Z country: BD mnt-routes: MAINT-ICCDHK-BD mnt-lower: MAINT-ICCDHK-BD source: APNIC rpki-ov-state: valid route6: 2400:e340::/32 descr: Kastech Computer Valley origin: AS136450 mnt-by: MAINT-KASTECH-BD country: BD mnt-routes: MAINT-KASTECH-BD mnt-lower: MAINT-KASTECH-BD last-modified: 2019-12-18T05:49:27Z source: APNIC rpki-ov-state: valid route6: 2400:e340:2::/48 descr: Kastech Computer Valley origin: AS136450 mnt-by: MAINT-KASTECH-BD country: BD mnt-routes: MAINT-KASTECH-BD mnt-lower: MAINT-KASTECH-BD last-modified: 2019-12-18T05:50:18Z source: APNIC rpki-ov-state: valid