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Comment by jpace121 | Hacker News Reader

You definitely notice the difference when dealing with mutable types in python, like lists.

  >> a = [1,2,3]
  >> b = a
  >> a.append(4)
  >> b #[1,2,3,4]

This is one of the things that throws off many beginners, and is an easy trap to fall into, not exotic at all.

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OP literally says this in the next sentence:

> But if a and b are both variables of the same Java class type, or Python lists, then after the assignment they refer to the same underlying object, so that if you make a change to a (e.g. by calling a class method on it, or appending an item to the list) then you see the same difference when you look at b.

His point is that there isn't a difference in python: in both cases you're just changing labels, but in the case of integers they're pointing to immutable objects.

That's why understanding when variable assignment gives you a reference vs. a copy is absolutely crucial to working with object-oriented languages.

Right, I was talking specifically about the integer case in Python

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