Keeping the Prime Numbers within 1 to 100, using a different method...

def keep_prime(L1):

    is_multiple = lambda x, y : x%y

    i = 1

    while i < len(L1):
        j = i + 1
        elem = L1[i]

        while j < len(L1):
            if not bool(is_multiple(L1[j], elem)):
                del L1[j]

            j += 1

        i += 1

    print(L1)

L2 = [i for i in range(1,101)]
keep_prime(L2)