Is it possible something like lvalue of perl or setf of lisp in python?

Question

In lisp you can say:

(setf (aref a 1) 5)

In perl you can say:

substr( $string, $start, $stop ) =~ s/a/b/g

Answer 1

No, there isn't any way to do this in general. The slice notation comes close in a limited case, as you can do things like this:

>>> a = [1, 2, 3]
>>> a[1:2] = [5, 6]
>>> a
[1, 5, 6, 3]