Pythonic way to check if a package is installed or not

Question

Pythonic way to check list of packages installed in Centos/Redhat?

In a bash script, I\'d do:

 rpm -qa | grep -w packagename

Answer 1

I could not get this answer: https://stackoverflow.com/a/51258124/498657 to work on Python 3.6.8, what did work for me was:

import sys
import rpm

ts = rpm.TransactionSet()
mi = ts.dbMatch( 'name', 'lsof' )

rpmhit=0
for h in mi:
    if h['name'] == 'lsof':
        rpmhit=1
        break

if rpmhit == 0:
    print('Error: Package lsof not installed. Install using: dnf install lsof')
    sys.exit(3)