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Confused with changing lists

I'm stuck on this weird thing in Python where changing one thing messes with another. But with other variables it works fine.

How do I fix this?

example = [1, 2, 3,4,5]
new = example
new[3] = 6
print(example)

Which outputs [1, 2, 3, 6, 5] instead of [1,2,3,4,5]

Solution

  • When you set new = example, you're essentially making both of them refer to the exact same memory location. Hence any change made to one will be seen in the other. We can correct this with

    new = example[:]

    Although in some cases you need to

    import copy
new = deepcopy(example)