Tuples look like lists but are immutable — once created, their elements cannot be reassigned. They are ideal for fixed records like coordinates or (key, value) pairs.
python point = (10, 20) x, y = point # unpacking single = (5,) # trailing comma required for one-element tuples
Because tuples are immutable and hashable (if their contents are), they can be used as dictionary keys, unlike lists.
python
balances = {("alice", "ETH"): 3.5}