ls = [50, 55, 57, 58, 60]

ls_size = int(len(ls) ** k)
temp = ["", "", ""]
final_ls = [temp for b in range(ls_size)]

j = 0
while j < 3:
    counter = 0
    for m in range(len(final_ls)):
        final_ls[m][j] = ls[counter]
        counter += 1
        if counter == 5:
            counter = 0
    j += 1
print(final_ls)