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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 use_tsig(self, keyring, keyname=None, algorithm=dns.tsig.default_algorithm):
 """Add a TSIG signature to the query. @param keyring: The TSIG keyring to use; defaults to None. @type keyring: dict @param keyname: The name of the TSIG key to use; defaults to None. The key must be defined in the keyring. If a keyring is specified but a keyname is not, then the key used will be the first key in the keyring. Note that the order of keys in a dictionary is not defined, so applications should supply a keyname when a keyring is used, unless they know the keyring contains only one key. @param algorithm: The TSIG key algorithm to use. The default is dns.tsig.default_algorithm. @type algorithm: string"""

        self.keyring = keyring
        if keyname is None:
            self.keyname = self.keyring.keys()[0]
        else:
            self.keyname = keyname
        self.keyalgorithm = algorithm