Some examples include:
lib.gitiles.change_log.ChangeLog,
lib.gitiles.change_log.FileChangeInfo,
crash.changelist_classifier.ChangelistClassifier,
crash.results.Result.

Also the region_info in findit/util_scripts/git_checkout/local_git_parsers.py as of http://crrev.com/2435863003#730001

Also maybe the commit_info (i.e., the values in that dict) for local_git_parsers.py? Though that one gets mutated a lot in the loop, so maybe it shouldn't be a namedtuple for the duration of the loop (though can be turned into one once we leave the loop).

Also the results of GetFileChangeInfo

The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra.git/+/9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386

commit 9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386
Author: wrengr <wrengr@chromium.org>
Date: Tue Nov 22 21:48:16 2016

Converting various classes to namedtuples

Also re-removing callstack.py, since a previous CL moved it into
stacktrace.py but somehow that got rebased improperly.

BUG= 661822 

Review-Url: https://codereview.chromium.org/2518663002

[delete] https://crrev.com/e5d7862c9beb05650a4405574c2cb28f33e87a3a/appengine/findit/crash/callstack.py
[modify] https://crrev.com/9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386/appengine/findit/crash/changelist_classifier.py
[modify] https://crrev.com/9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386/appengine/findit/crash/results.py
[modify] https://crrev.com/9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386/appengine/findit/crash/stacktrace.py
[delete] https://crrev.com/e5d7862c9beb05650a4405574c2cb28f33e87a3a/appengine/findit/crash/test/callstack_test.py
[modify] https://crrev.com/9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386/appengine/findit/crash/test/results_test.py
[modify] https://crrev.com/9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386/appengine/findit/crash/test/stacktrace_test.py
[modify] https://crrev.com/9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386/appengine/findit/lib/gitiles/change_log.py
[modify] https://crrev.com/9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386/appengine/findit/util_scripts/git_checkout/local_git_parsers.py
[modify] https://crrev.com/9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386/appengine/findit/util_scripts/git_checkout/test/local_git_parsers_test.py
[modify] https://crrev.com/9cacec9460f8fbcbb6cfe2f4bb4def59c3fc6386/appengine/findit/util_scripts/git_checkout/test/local_git_repository_test.py

I think I got them all. If there are any other classes we should convert, then either reopen this ticket or make a new one.

The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra.git/+/492dc572d8c069d93e82b7577d8e6a67ce5e16b1

commit 492dc572d8c069d93e82b7577d8e6a67ce5e16b1
Author: wrengr <wrengr@chromium.org>
Date: Tue Dec 27 19:20:45 2016

Converting Region class to a namedtuple

BUG= 661822 
TBR=stgao@chromium.org

Review-Url: https://codereview.chromium.org/2607613002

[modify] https://crrev.com/492dc572d8c069d93e82b7577d8e6a67ce5e16b1/appengine/findit/crash/changelist_classifier.py
[modify] https://crrev.com/492dc572d8c069d93e82b7577d8e6a67ce5e16b1/appengine/findit/libs/gitiles/blame.py
[modify] https://crrev.com/492dc572d8c069d93e82b7577d8e6a67ce5e16b1/appengine/findit/libs/gitiles/change_log.py