Comment 1 for bug 921990

thank, Yagnesh,

pasting below from
https://code.launchpad.net/~yagnesh/python-mode/py-shell et al

> So you mean to say py-shell-name has no business in calling shell and its only for come as 'default' if all others fail?

Basically.
Having multiple choices, you can't avoid some hierarchical order making
a selection.

if hard-coded `py-shell-name' always should prevail, you must it change
when executing code designed for a different Python by shebang.

The assumtion so far: shebang knows best which Python to use. Therefor
preceding by default.

Will consider possible change of py-execute-region permitting to enforce
a shell independent from shebang, accepting an optional argument "execute-with-this-shell-instead-of-shebang",
would replace "&optional async"