Python standard library: built-in functions frozenset ([iterable]), frozensetiterable

Python standard library: built-in functions frozenset ([iterable]), frozensetiterable

This function returns a frozen set. The so-called freeze means that this set can no longer add or delete any elements in the set. Therefore, the difference with set is that set can add or delete elements, but frozenset cannot. Frozenset is mainly used for fast speed and is implemented using the hash algorithm. The iterable parameter is an object that can be iterated, such as the list, dictionary, and tuples.

Example:

# Frozenset () l = [1, 2, 3, 4, 5, 6, 6, 7, 8, 9] print (len (l), l) set = frozenset (l) print (len (set), set)

The output is as follows:

11 [1, 2, 3, 4, 5, 6, 6, 7, 8, 8, 9]

9 frozenset ({1, 2, 3, 4, 5, 6, 7, 8, 9 })

 

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