> Java has primitive types, for which it is a copy. But it's more accurate IMO to attribute this as a property of names, rather than a property of assignment. Python's names (and most Java values, and some C# values) have reference semantics. Having understood that properly, saying that Python (like Java) is "pass by assignment" then just follows naturally, and all the usual confusion around this point vanishes. Passing an argument to a function is simply assigning it to the corresponding parameter. (C++'s idea of "references" in the type system is far more complex IMO - e.g. https://langdev.stackexchange.com/q/3798/_/3807#3807 .)

I use pass-by-label for this term, after a visual demonstration of variables that showed them as labels that attach to different values/objects. But I like "pass-by-assignment" a lot — it gives the correct intuition that whatever is happening when I do `x = 5` is also happening when I do `def func(x): pass; func(5)`.