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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_next_token(self, length=15, **kwargs):
 """Gets the next available token. :param length: length of the token :param kwargs: additional filter criteria to check for when looking for a unique token. """

        return self.get_available_tokens(count=1,
                                         token_length=length,
                                         **kwargs)[0]