If Python were fully call by reference then: def g(y): y = 3 x = 10 g(x) x # => ?? If it's 3 then it's pass by reference here, if it's 10 it's pas

If Python were fully call by reference then: def g(y): y = 3 x = 10 g(x) x # => ?? If it's 3 then it's pass by reference here, if it's 10 it's pass by reference. Which is it? Additionally, for something to be a closure it has to close over something (an environment). What does `f` or `g` close over? Note that they aren't changing any environment, they are "merely" functions, not closures. Python does have closures, but those aren't examples of them. And being able to assign a function to a variable does not make a closure, or do you think that C has closures because it has function pointers?