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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_algorithm(algorithm):
 """Returns the wire format string and the hash module to use for the specified TSIG algorithm @rtype: (string, hash constructor) @raises NotImplementedError: I{algorithm} is not supported """


    global _hashes
    if _hashes is None:
        _setup_hashes()

    if isinstance(algorithm, (str, unicode)):
        algorithm = dns.name.from_text(algorithm)

    if sys.hexversion < 0x02050200 and \
       (algorithm == HMAC_SHA384 or algorithm == HMAC_SHA512):
        raise NotImplementedError("TSIG algorithm " + str(algorithm) +
                                  " requires Python 2.5.2 or later")

    try:
        return (algorithm.to_digestable(), _hashes[algorithm])
    except KeyError:
        raise NotImplementedError("TSIG algorithm " + str(algorithm) +
                                  " is not supported")