Virt-who service fails to start on Red Hat Satellite 6.x with a 'ImportError: cannot import name DependencyWarning' error

Issue

Virt-who service fails to start on Red Hat Satellite 6.x with the following error:

# systemctl status virt-who.service
● virt-who.service - Daemon for reporting virtual guest IDs to subscription-manager
   Loaded: loaded (/usr/lib/systemd/system/virt-who.service; enabled; vendor preset: disabled)
   Active: failed (Result: exit-code) since Tue 2022-05-10 13:32:03 EET; 39min ago
  Process: 69849 ExecStart=/usr/bin/virt-who (code=exited, status=1/FAILURE)
 Main PID: 69849 (code=exited, status=1/FAILURE)


May 10 13:32:03 satellite.example.com virt-who[69849]: import virtwho.main
May 10 13:32:03 satellite.example.com virt-who[69849]: File "/usr/lib/python2.7/site-packages/virtwho/main...le>
May 10 13:32:03 satellite.example.com virt-who[69849]: import requests
May 10 13:32:03 satellite.example.com virt-who[69849]: File "/usr/lib/python2.7/site-packages/requests/__i...le>
May 10 13:32:03 satellite.example.com virt-who[69849]: from urllib3.exceptions import DependencyWarning
May 10 13:32:03 satellite.example.com virt-who[69849]: ImportError: cannot import name DependencyWarning
May 10 13:32:03 satellite.example.com systemd[1]: virt-who.service: main process exited, code=exited, sta...LURE
May 10 13:32:03 satellite.example.com systemd[1]: Failed to start Daemon for reporting virtual guest IDs ...ger.
May 10 13:32:03 satellite.example.com systemd[1]: Unit virt-who.service entered failed state.
May 10 13:32:03 satellite.example.com systemd[1]: virt-who.service failed.
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