Only immutable elements can be used as dictionary keys, and hence only tuples and not lists can be used as keys.

How tuples can be used as keys in dictionaries?

Because tuples are hashable and lists are not, if we want to create a composite key to use in a dictionary we must use a tuple as the key. ... This loop traverses the keys in directory , which are tuples. It assigns the elements of each tuple to last and first , then prints the name and corresponding telephone number.

Is tuple a dictionary?

A dictionary is a hash table of key-value pairs. List and tuple is an ordered collection of items. ... List and dictionary objects are mutable i.e. it is possible to add new item or delete and item from it. Tuple is an immutable object.