Input an array of numbers, and build a function in Python to replace all even numbers with 0.
[4, 10, 15, 20]
def replace_even(arr):
    for i in range(len(arr)):
        if arr[i] % 2 == 0:
            arr[i] = 0
    return arr

result = replace_even([4, 10, 15, 20])
print(result)