x = foo(y:=bar(), baz(), y) or z should work assuming foo bar and baz are functions being called?

if this is setting y to the effect of bar() + running baz after, then:

x = [bar(), baz()][0] or z

might work

and if you need y to be defined for later use:

x = [(y:=bar()), baz()][0] or z

but thats from memory, not sure if that will even run as written.

if I get to a real computer I'll try that with an actual if statement instead of a bastardized ternary.