Split a list every Nth element

Split a list every Nth element.
Sample list:
[‘a’, ‘b’, ‘c’, ‘d’, ‘e’, ‘f’, ‘g’, ‘h’, ‘i’, ‘j’, ‘k’, ‘l’, ‘m’, ‘n’]
Expected otput (N=3):
[[‘a’, ‘d’, ‘g’, ‘j’, ‘m’], [‘b’, ‘e’, ‘h’, ‘k’, ‘n’], [‘c’, ‘f’, ‘i’, ‘l’]]
def list_slice(S, step):
    return [S[i::step] for i in range(step)]

# test
L = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n']

print(list_slice(L, 3))

Output:

[['a', 'd', 'g', 'j', 'm'], ['b', 'e', 'h', 'k', 'n'], ['c', 'f', 'i', 'l']]