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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 compute_auth_key(userid, password):
 """ Compute the authentication key for freedns.afraid.org. This is the SHA1 hash of the string b'userid|password'. :param userid: ascii username :param password: ascii password :return: ascii authentication key (SHA1 at this point) """

    import sys
    if sys.version_info >= (3, 0):
        return hashlib.sha1(b"|".join((userid.encode("ascii"),  # noqa: S303
                                       password.encode("ascii")))).hexdigest()
    return hashlib.sha1("|".join((userid, password))).hexdigest()