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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 pos_tokenize(self: object, fileids: str):
 """ Segments, tokenizes, and POS tag a document in the corpus. """

        for para in self.paras(fileids):
            yield [
                self.pos_tagger(word_tokenize(sent))
                for sent in sent_tokenize(para)
            ]