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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_cipher_key(keyfile=None):
 """ Create key which will be used in des, because des need 8bytes chars """

    _key = get_key(keyfile)
    _k = md5(_key).hexdigest()
    key = xor(_k[:8], _k[8:16], _k[16:24], _k[24:])
    return key