[Python-Dev] #!/usr/bin/env python --> python3 where applicable

[Stephen J. Turnbull]

Nick Coghlan writes:

 > 3. Change the shebang lines in Python standard library scripts to be
 > version specific and update release.py to fix them all when bumping the
 > version number in the source tree.

+1

I think that it's probably best to leave "python", "python2", and
"python3" for the use of downstream distributors.  ISTR that was what
Guido concluded, in the discuss that led to Python 3 defaulting to
altinstall---it wasn't just convenient because Python 3 is a major
change, but that experience has shown that deciding which Python is
going to be "The python" on somebody's system just isn't a decision
that Python should make.

Sure, the difference between Python 2 and Python 3 is big enough to be
a hairy nuisance 95% of the time, while the difference between Python
2.5 and Python 2.6 is so only 5% of the time.  But the fact is that
incompatibilities arise with a minor version bump, too, and all the
major distros that I know about have some way to select the default
Python version that will be "python".  That's not because they want to
distinguish between Python 2 and Python 3, nor between Python 2 and
Python 1.