[rcthompson]

Just to note, the new compact dicts in Python 3.6 are apparently based on the PyPy dict implementation: https://docs.python.org/3.6/whatsnew/3.6.html#other-language...

[raymondh]

More properly, both the CPython 3.6 and PyPy compact dicts are based on this proposal: https://mail.python.org/pipermail/python-dev/2012-December/1... and this proof of concept: http://code.activestate.com/recipes/578375