why () is () and [] is [] work in other way?

[Paul Rubin]

Nobody <nobody at nowhere.com> writes:
> All practical languages have some implementation-defined behaviour, often
> far more problematic than Python's.

The usual reason for accepting implementation-defined behavior is to
enable low-level efficiency hacks written for specific machines.  C and
C++ are used for that sort of purpose, so they leave many things
implementation-defined.  Python doesn't have the same goals and should
leave less up to the implementation.  Java, Ada, Standard ML, etc.  all
try to eliminate implementation-defined behavior in the language much
more than Python does.  I don't have any idea why you consider that to
be "throwing the baby out with the bath water".