
def get_primes(n):
    primes = []
    min_div = [0] * n
    for q in xrange(2, n):
        if min_div[q] == 0:
            primes.append(q)
            min_div[q] = q
        for p in primes:
            if p > min_div[q] or p * q >= n:
                break
            assert min_div[p * q] == 0 
            min_div[p * q] = p
    return primes

def find_twins(primes):
    for i in xrange(1, len(primes)):
        if primes[i] - primes[i - 1] == 2:
            yield (primes[i - 1], primes[i])

print list(find_twins(get_primes(200)))