List comprehension with lambda function

Question

def multipliers():
    return [lambda x: i * x for i in range(4)]


print([m(1) for m in multipliers()]) # [3, 3, 3, 3]

Why it's not [0, 1, 2, 3]? Can't understand. So, for some reason we have i = 3 in all lambdas? Why?

Answer 1

This is because of Pythons late binding closures. You can fix the issue by writing:

def multipliers():
    return [lambda x, i=i : i * x for i in range(4)]

Answer 2

Is this what you were trying to do?

def multipliers(x):
    return [i * x for i in range(4)]

print(multipliers(1)) 

>> [0, 1, 2, 3]