Die, python2, die.
Some generated .java files change (parameterized automata for
spell-correction).
This is because the order of python dictionaries was not well-defined
previously. A sort() was added so that the python code now generates
reproducible output (Thanks @mikemccand).
So we'll suffer a change once, but the automata are equivalent. If you
run the script again you should not see source code changes.
The relevant unit tests are exhaustive (if you trust the paper!), so we can
be confident it does not break things, even though it looks very scary.
On newer linux distros, at least, 'python' now means python3. So
we can't rely on what version of python it will invoke (at least for a
few years).
For example in Fedora Linux:
https://fedoraproject.org/wiki/Changes/Python_means_Python3
For python2.x code, explicitly call 'python2.7' and for python3.x code,
explicitly call 'python3'.
Ant variable names are cleaned up, e.g. 'python.exe' is renamed to
'python2.exe' and 'python32.exe' is renamed to 'python3.exe'. This also
makes it easy to identify remaining python 2.x code that should be
migrated to python 3.x
