Пример кода тут:
numbers = [3, 4, 2, 7, 2, 3, 8, 3, 1, 9]
A = [x**2 for x in numbers if x % 2 == 0]
print(A) # [16, 4, 4, 64]
B = [x**2 if x % 2 == 0 else x ** 3 for x in numbers]
print(B) # [27, 16, 4, 343, 4, 27, 64, 27, 1, 729]
numbers = [3, 4, 2, 7, 2, 3, 8, 3, 1, 9]
A = [x**2 for x in numbers if x % 2 == 0]
print(A) # [16, 4, 4, 64]
B = [x**2 if x % 2 == 0 else x ** 3 for x in numbers]
print(B) # [27, 16, 4, 343, 4, 27, 64, 27, 1, 729]