#4 most askedVery commonMediumData types & mutability

Mutable vs immutable types and references

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Which Python types are mutable? How does that affect passing them to functions? Predict the output.

🔮 Predict the output

def update(n, items):
    n += 1
    items.append(n)

count = 1
data = []
update(count, data)
print(count, data)

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