Installed Python 3 on Mac OS X Yosemite but its still Python 2.7

[Cem Karan]

On Mar 7, 2015, at 6:39 PM, James Dekker <james.dekker at gmail.com> wrote:

> I am currently running OS X Yosemite (10.10.2) on my MacBook Pro... By default, Apple ships Python 2.7.6 on Yosemite.
> 
> Just downloaded and ran this installer for Python 3:
> 
> python-3.4.3-macosx10.6.pkg
> 
> When I opened up my Terminal and typed in python, this is what came up:
> 
> Python 2.7.6 (default, Sep  9 2014, 15:04:36)
>  
> 
> [GCC 4.2.1 Compatible Apple LLVM 6.0 (clang-600.0.39)]
>  on darwin
> 
> Type "help", "copyright", "credits" or "license" for more information.
> >>>
> Sorry, I am very new to Python...
> 
> Question(s):
> 
> (1) Does anyone know where the Python 3.4.3 interpreter was installed?

It should be installed as either python3 or python3.4.  To figure out which, type 'python' in the terminal, and hit tab twice.  It should bring up a list of python interpreters you have installed.

> (2) Do I need to uninstall Python 2.7.3 (if so, how do I go about doing this) before setting a global environmental variable such as PYTHON_HOME to the location of the installed Python 3.4.3?

You don't need to uninstall python 2.7, and you shouldn't try.  I tried it as an experiment at one time, and my system had various mysterious failures after that. It may be that Yosemite fixes those failures, but I wouldn't bet on it.

Thanks,
Cem Karan