def use(self, algorithm):
        """Change the hash algorithm you gonna use.
        """
        algorithm = algorithm.lower()
        if algorithm == "md5":
            self.default_hash_method = hashlib.md5
        elif algorithm == "sha1":
            self.default_hash_method = hashlib.sha1
        elif algorithm == "sha224":
            self.default_hash_method = hashlib.sha224
        elif algorithm == "sha256":
            self.default_hash_method = hashlib.sha256
        elif algorithm == "sha384":
            self.default_hash_method = hashlib.sha384
        elif algorithm == "sha512":
            self.default_hash_method = hashlib.sha512
        else:
            raise WrongHashAlgorithmError("There's no algorithm names '%s'! "
                                          "use one of 'md5', 'sha1', 'sha224', "
                                          "'sha256', 'sha384', 'sha512'." % algorithm)
Change the hash algorithm you gonna use.