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So, you might wonder why are we making such a big deal out of

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whether a and b point to the same object or two objects that are equivalent?

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The answer is that, when they are aliases for each other,

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when they point to the same object,

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things can get pretty confusing because when you change one of the objects,

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you've changed the other one too.

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So, let's just see how that works out.

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On line one, so the variable a is bound to the list 81, 82,

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83 and b is bound to an equivalent list,

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but not the same one.

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So, when we get to line three,

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it says print a as b the answer is false.

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Now, on line five,

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we're going to make b and a be aliases for each other.

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They weren't before, but now they are.

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So, b is no longer going to be bound to that one,

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it's going to be bound to the thing that a is bound to.

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Now, a is equivalent to b,

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but we also have that a and b are bound to the very same object.

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If we then set b square bracket zero to equal five,

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well this is position zero,

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position one, position two.

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If we set b square bracket zero to now have the value five,

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and then we go to print a,

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we're going to get five, 82, 83.

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The reason I say this is confusing is if you look at

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this code from the top to the bottom,

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we set a to be 81, 82,

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and 83, we never change a again.

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There's no assignment statement to a anywhere in here.

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Then we go print it, and it's different.

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Now in this code, a and b they're all pretty close to each other.

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We can figure out what's going on.

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But you can imagine a much bigger program where you have a variable,

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and somewhere else in the code,

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some other alias for that variable causes the item do mutated to change,

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and you have no idea why it's happening.

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So, that's why I say aliasing and mutable objects can create some confusions.

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Be on the lookout for that. See you next time.