all Python 3Sets (set)function

frozenset.copy

frozenset

For an immutable frozenset, copy() returns the same object (nothing to copy).

Syntax

f.copy()

The method exists for interface parity: code that accepts any set can call copy() without checking whether it got a set or a frozenset. There is nothing to protect from mutation, so no new object is built — you get the original back. When you need a copy you can actually modify, use set(f); copy() will never hand you a mutable one.

Examples

f = frozenset({1, 2})
print(f.copy() is f)   # → True
print(f.copy())   # → frozenset({1, 2})
print(frozenset().copy())   # → frozenset()
s = {1, 2}
print(s.copy() is s)   # → False

See also

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