reduce() is not a builtin in python 3

[ericvaandering]

See https://docs.python.org/2/library/functools.html

moved to functools as of python 2.6.

[cmsbuild]

A new Pull Request was created by @ericvaandering (Eric Vaandering) for CMSSW_8_0_X.

reduce() is not a builtin in python 3

It involves the following packages:

CondCore/TagCollection
Configuration/Applications
DQM/Integration
Documentation/DataFormats
HLTriggerOffline/Egamma
RecoLuminosity/LumiDB
Utilities/RelMon
Validation/Performance
Validation/Tools

@smuzaffar, @diguida, @danduggan, @cvuosalo, @cmsdoxy, @cerminar, @cmsbuild, @franzoni, @Dr15Jones, @deguio, @slava77, @ggovi, @mmusich, @vanbesien, @davidlange6 can you please review it and eventually sign? Thanks.
@ghellwig, @apfeiffer1, @batinkov, @wddgit, @Martin-Grunewald, @threus this is something you requested to watch as well.
You can sign-off by replying to this message having '+1' in the first line of your reply.
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[Dr15Jones]

Please test

[Dr15Jones]

+1

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/9096/console

[cmsbuild]

+1
Tested at: 00f5de7
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-12007/9096/summary.html

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-12007/9096/summary.html

[slava77]

+1

for #12007 00f5de7

• changes are as described
  • there are only 15 actual non-trivial line diffs
  • it's unclear if this will merge transparently with Replace has_key with in for dictionaries #12004 (large white-space edits in the same file)
• jenkins tests pass and comparisons with baseline show no differences