размер набора питона
n = len({1, 2, 3})
# n = 3
or
myset = set()
myset.add(1)
myset.add(2)
myset.add(3)
len(set1)
# len(set1) = 3
Bacem OBEY
n = len({1, 2, 3})
# n = 3
or
myset = set()
myset.add(1)
myset.add(2)
myset.add(3)
len(set1)
# len(set1) = 3a = {1, 2, 3, 4, 5, 6}
len(a)