Getting following error while running https://www.erp5.com/erp5-HowTo.Request.Erp5.On.Command.Line#linux-installer 

TASK [repository : Install Ubuntu 16.04 repository] **************************** fatal: [localhost]: FAILED! => {"changed": false, "failed": true, "msg": "Failed to auto-install python-apt. Error was: 'W: The repository 'http://ppa.launchpad.net/beineri/opt-qt561-xenial/ubuntu xenial Release' does not have a Release file.\nE: Failed to fetch http://ppa.launchpad.net/beineri/opt-qt561-xenial/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found\nE: Some index files failed to download. They have been ignored, or old ones used instead.'"}

PLAY RECAP *********************************************************************

localhost : ok=2 changed=1 unreachable=0 failed=1

 Can someone please guide?