Proper shebang for python3

[Christian Gollwitzer]

Am 21.07.19 um 07:31 schrieb Tim Daneliuk:
> On 7/20/19 6:04 PM, Chris Angelico wrote:
>> Are you aware of every systemwide command that happens to be
>> implemented in Python, such that you won't execute any of them while
>> you have the venv active?
> 
> No, but this has never been a problem because the newer versions of
> python tend to be pretty good - within a major release tree - of being
> backward compatible.  Certainly, if I were running, say, RedHat 4 with
> a very new version of python in my path first, this could theoretically
> be an issue.  I've just not run into it.
> 

It's not about the core language, but these system tools depend on 
packages, sometimes specialist packages, which might not be available in 
your venv.

	Christian