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#1 most askedVery commonMediumData types & mutability

The mutable default argument trap

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def add_item(item, basket=[]):
    basket.append(item)
    return basket

add_item("apple")
print(add_item("pear"))

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    def add_item(item, basket=None):
    if basket is None:
        basket = []
    basket.append(item)
    return basket

add_item("apple")
print(add_item("pear"))
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