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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(self, index, tag=LEMMA):
 """ Returns a tag for the word at the given index. The tag can be WORD, LEMMA, POS, CHUNK, PNP, RELATION, ROLE, ANCHOR or a custom word tag. """

        if tag == WORD:
            return self.words[index]
        if tag == LEMMA:
            return self.words[index].lemma
        if tag == POS:
            return self.words[index].type
        if tag == CHUNK:
            return self.words[index].chunk
        if tag == PNP:
            return self.words[index].pnp
        if tag == REL:
            ch = self.words[index].chunk; return ch and ch.relation
        if tag == ROLE:
            ch = self.words[index].chunk; return ch and ch.role
        if tag == ANCHOR:
            ch = self.words[index].pnp; return ch and ch.anchor
        if tag in self.words[index].custom_tags:
            return self.words[index].custom_tags[tag]
        return None