$ sudo apt list --installed |grep pgpool

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

libpgpool2/focal-pgdg,now 4.3.5-1.pgdg20.04+1 amd64 [installed]
pgpool2/focal-pgdg,now 4.3.5-1.pgdg20.04+1 amd64 [installed]
postgresql-14-pgpool2/focal-pgdg,now 4.3.5-1.pgdg20.04+1 amd64 [installed]




$ cat /etc/*os*rel*
NAME="Ubuntu"
VERSION="20.04.5 LTS (Focal Fossa)"
ID=ubuntu
ID_LIKE=debian
PRETTY_NAME="Ubuntu 20.04.5 LTS"
VERSION_ID="20.04"
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
VERSION_CODENAME=focal
UBUNTU_CODENAME=focal