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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 tag_one(self: object, tokens: List[str], index: int, history: List[str]):
 """ Determine an appropriate tag for the specified token, and return that tag. If this tagger is unable to determine a tag for the specified token, then its backoff tagger is consulted. :rtype: tuple :type tokens: list :param tokens: The list of words that are being tagged. :type index: int :param index: The index of the word whose tag should be returned. :type history: list(str) :param history: A list of the tags for all words before index. """

        lemma = None
        for tagger in self._taggers:
            lemma = tagger.choose_tag(tokens, index, history)
            if lemma is not None:
                break
        return lemma, tagger