1# basic sets
2
3try:
4    frozenset
5except NameError:
6    print("SKIP")
7    raise SystemExit
8
9s = frozenset()
10print(s)
11
12s = frozenset({1})
13print(s)
14
15s = frozenset({3, 4, 3, 1})
16print(sorted(s))
17
18# frozensets are hashable unlike sets
19print({frozenset("1"): 2})
20