Arch switched from Python 2 to Python 3, keeping the /usr/bin/python binary as pointing to their newest version of Python before the convention of naming it /usr/bin/python3 was standardised.
It was specifically in response to the troubles caused by having /usr/bin/python be python3 in Arch that the guideline came about: http://legacy.python.org/dev/peps/pep-0394/
It was specifically in response to the troubles caused by having /usr/bin/python be python3 in Arch that the guideline came about: http://legacy.python.org/dev/peps/pep-0394/