Great article.
I think the example for the walrus operator could be better. Something like
# We want to increment by the number if it's nonzero, otherwise we want to increment by at least 1
x = get_some_number_maybe_0()
if x:
y += x
else:
y += 1
Which can be transformed with walrus operator to:
if x := get_some_number_maybe_0():
y += x
else:
y += 1
If the example you've shown, should_run isn't necessary, you can just base the if statement on the return of the os.environ call.
I guess the above could also be done as y += max(1, get_some_number_maybe_0()). Dammit, I need to stop finding ways to optimize my examples :P
Edit: The PEP introducing the operator has some better, albeit more complicated examples python.org/dev/peps/pep-0572