[BuildRules] cleanup PYTHON27; use python3 as default

[smuzaffar]

• Build Rules
  • Remove PERL code and perl dependency in build rules
  • Use python3 as default for CompilePython rule. So no more python2 compatibility
• Cleanup cmsdist for PYTHON27PATH related stuff

[cmsbuild]

A new Pull Request was created by @smuzaffar (Malik Shahzad Muzaffar) for branch IB/CMSSW_12_0_X/master.

@cmsbuild, @smuzaffar, @mrodozov, @iarspider can you please review it and eventually sign? Thanks.
@silviodonato, @dpiparo, @qliphy, @perrotta you are the release manager for this.
cms-bot commands are listed here

[smuzaffar]

test parameters:

• full_cmssw = true

[smuzaffar]

please test

[smuzaffar]

please test

[cmsbuild]

-1

Failed Tests: UnitTests
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-6316da/16963/summary.html
COMMIT: d135cfa
CMSSW: CMSSW_12_0_X_2021-07-18-0000/slc7_amd64_gcc900
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week0/cms-sw/cmsdist/7146/16963/install.sh to create a dev area with all the needed externals and cmssw changes.

The following merge commits were also included on top of IB + this PR after doing git cms-merge-topic:

• @bsunanda Run3-gex83A Make a few SD's in SimG4CMS/Forward with the new way of initiation cmssw#34507
• @VinInn Lin log chi2 cut for patatrack cmssw#34419
• @mmusich fix test_getPayloadData in case there've been recent changes in the plugins definitions cmssw#34515
• @bsunanda Run3-sim88 Make use of ESGetToken in a number of Analyzers used for SIM data cmssw#34405
• @jfernan2 [DQM] Add dqmPerLSsaving modifier cmssw#34487
• @wddgit Implement persistence for ProcessBlock products cmssw#33969
• @cms-sw Revert "Revert "Run3-gex83B Convert all SD's in SimG4CMS/ShowerLibraryProducer using the new way of initiating"" cmssw#34537
• @cvuosalo [DD4hep] Enable Run 3 DD4hep DB workflow with correct GT for PR & IB tests cmssw#34526

You can see more details here:
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-6316da/16963/git-recent-commits.json
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-6316da/16963/git-merge-result

Unit Tests

I found errors in the following unit tests:

---> test TestDQMServicesDemo had ERRORS

Comparison Summary

@slava77 comparisons for the following workflows were not done due to missing matrix map:

• /data/cmsbld/jenkins/workspace/compare-root-files-short-matrix/data/PR-6316da/11634.912_TTbar_14TeV+2021_DD4hepDB+TTbar_14TeV_TuneCP5_GenSim+Digi+Reco+HARVEST+ALCA

Summary:

• No significant changes to the logs found
• Reco comparison results: 4 differences found in the comparisons
• DQMHistoTests: Total files compared: 38
• DQMHistoTests: Total histograms compared: 2786302
• DQMHistoTests: Total failures: 6
• DQMHistoTests: Total nulls: 1
• DQMHistoTests: Total successes: 2786273
• DQMHistoTests: Total skipped: 22
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: -0.004 KiB( 37 files compared)
• DQMHistoSizes: changed ( 312.0 ): -0.004 KiB MessageLogger/Warnings
• Checked 160 log files, 37 edm output root files, 38 DQM output files
• TriggerResults: no differences found