running other older versions of python

[Skaperen]

So VM's or other messy stuff like install to OS,is needed if don't want use a easy version management like pyenv.

but pyenv also needs install to OS ... install of other versions of Python to my primary OS, which i do not want to do.

there are 8 different versions of Python i have identified that i want to have running (2.4, 2.5, 2.6, 2.7, 3.3, 3.4, 3.5, 3.6). since i don't want a mix (until i have tested everything in a mix) that means at least one virtual machine (a mix there is OK). but once i do that, it is easy enough to duplicate VMs to have 8 VMs and install just one version of Python on each. the reson i would have 8 VMs instead of 6 is so that i can run what i have on my main system each in a VM for very consistent comparison and the ability to easily test if the VM, its guest OS, or its installation of Python (probably a compile from source) is the cause of an issue. 9 VMs when 3.7 is released.