Mastering-Python-2e-code_2/CH_05_functional_programming/T_03_set_comprehensions.rst

>>> [x*y for x in range(3) for y in range(3)]
[0, 0, 0, 0, 1, 2, 0, 2, 4]

>>> {x*y for x in range(3) for y in range(3)}
{0, 1, 2, 4}