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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 encode(self, key):
 """Encodes a user key into a particular format. The result of this method will be used by swauth for storing user credentials. If salt is not manually set in conf file, a random salt will be generated and used. :param key: User's secret key :returns: A string representing user credentials """

        salt = self.salt or os.urandom(32).encode('base64').rstrip()
        return self.encode_w_salt(salt, key)