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My brother Nate continues to fight stage IV Hodgkin's lymphoma. He's just 31, with a wife and baby girl. They have no active income (since he's been unable to return to work), no insurance, and cannot afford the treatment he needs. Nate and his family need your help. Please consider a donation, every dollar helps. Thanks.

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Python       Report abuse 

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def blocks(data, blocksize):
    """Generator that yields elements from xs in blocks."""
    assert(len(data) % blocksize == 0)
    for i in xrange(0, len(data), blocksize):
        yield data[i:i+blocksize]

key1 = list(blocks("ABCDEFGHIKLMNOPQRSTUVWXYZ", 5))
key2 = list(blocks("37FBO7T20KZUMXYHLS196QW4AVIDGNJPCRE5", 6))

def code2char(a, b, key):
    return key[a][b]

def char2code(c, key):
    c = c.upper()
    r = [c in row for row in key]
    assert any(r)
    a = r.index(True)
    b = key[a].index(c)
    return a, b

def encrypt(s, key):
    codes = map(lambda x: char2code(x,key), s)
    a, b = zip(*codes)
    d = blocks(a+b, 2)
    c = "".join(map(lambda (a,b): code2char(a, b, key), d))
    return c

def decrypt(c, key):
    d = sum(map(lambda x: char2code(x,key), c), ())
    h = len(d)/2
    a, b = d[:h], d[h:]
    codes = zip(a, b)
    s = "".join(map(lambda (a,b): code2char(a,b,key), codes))
    return s