AttributeError: 'odict_keys' object has no attribute 'sort'

[rcochran@dev4 reposurgeon-workdir] $ make
(cd the-svn-repo-mirror/ >/dev/null; repotool export) >the-svn-repo.svn
python3 /home/rcochran/Programming/reposurgeon/reposurgeon "verbose 1" "script the-svn-repo.opts" "read  <the-svn-repo.svn" "authors read <the-svn-repo.map" "sourcetype svn" "prefer git" "script the-svn-repo.lift" "legacy write >the-svn-repo.fo" "write >the-svn-repo.fi"
reposurgeon: verbose 1
reposurgeon: from the-svn-repo.svn...+++-...(2.821s sec) done.
Traceback (most recent call last):
  File "/home/rcochran/Programming/reposurgeon/reposurgeon", line 14006, in <module>
    main()
  File "/home/rcochran/Programming/reposurgeon/reposurgeon", line 13996, in main
    cmd.Cmd.onecmd(interpreter, interpreter.precmd(arg))
  File "/usr/lib64/python3.6/cmd.py", line 217, in onecmd
    return func(arg)
  File "/home/rcochran/Programming/reposurgeon/reposurgeon", line 10367, in do_read
    repo.fast_import(parse.stdin, parse.options, progress=(verbose==1 and not quiet))
  File "/home/rcochran/Programming/reposurgeon/reposurgeon", line 6328, in fast_import
    StreamParser(self).fast_import(fp, options, progress, source=source)
  File "/home/rcochran/Programming/reposurgeon/reposurgeon", line 3996, in fast_import
    self.svn_process(options, baton)
  File "/home/rcochran/Programming/reposurgeon/reposurgeon", line 4272, in svn_process
    reverso.sort(reverse=True)
AttributeError: 'odict_keys' object has no attribute 'sort'
make: *** [Makefile:56: the-svn-repo.fi] Error 1

Seems like the last commit introduced this. I'm using Python 3, but it is happening with Python 2 as well. I don't have PyPy on this machine, so I haven't tried that.