Multiple versions of Python coexisting in the same OS

[Edward Diener]

On 7/25/2010 1:51 PM, Joel Goldstick wrote:
> Edward Diener wrote:
>> Are there any documents about multiple versionsof Python coexisting in
>> the same OS ( Windows in my case ) and what pitfalls to look out for ?
>> I have already run into a number of them. I installed Python 2.7 and
>> 3.1.2 into completely folders, but immediately ran into serious
>> problems executing a Python script.
>>
>> The first problem is that just invoking Python will start whichever
>> version is first in the PATH, and this is true from the command line
>> or internally in a Python script.
>>
>> The second problem is that invoking a script ( some xxx.py ) will
>> start whichever version of Python is associated with the .py extension.
>>
>> The third problem is if some software expects its scripts, which it
>> puts in some Python subdirectory to be in the PATH.
>>
>> There may be other considerations but overall having to versions
>> coexisting has turned out to be a big headache involving both changes
>> in the PATH and in the .py association.
>>
>> Does anybody know of other things to look out for ?
>
> There is this:
> http://pypi.python.org/pypi/virtualenv

It appears to be only for Linux.