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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_subhash(hash):
 """Get a second hash based on napiprojekt's hash. :param str hash: napiprojekt's hash. :return: the subhash. :rtype: str """

    idx = [0xe, 0x3, 0x6, 0x8, 0x2]
    mul = [2, 2, 5, 4, 3]
    add = [0, 0xd, 0x10, 0xb, 0x5]

    b = []
    for i in range(len(idx)):
        a = add[i]
        m = mul[i]
        i = idx[i]
        t = a + int(hash[i], 16)
        v = int(hash[t:t + 2], 16)
        b.append(('%x' % (v * m))[-1])

    return ''.join(b)