Tuples are immutable, but that doesn't mean they can't contain references to mutable objects. When you want to use a tuple as a key in a dictionary, Python che

Tuples are immutable, but that doesn't mean they can't contain references to mutable objects. When you want to use a tuple as a key in a dictionary, Python checks if all members of the tuple are immutable. If one or more of them aren't, you'll get an 'unhashable type' error.