Suggestions

1.  Put result on output line.  I understand that this depends on consistent ordering of keys.  Have nose skip this doctest by adding `# doctest: +SKIP` to the end of the line.  
2.  You could then add this test into `test_core.py`.  Also, is there anything else we  should test about this function?
2.  See if it's possible to keep the input on one line (not a big deal though).