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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 ensureFulltextIndex(self, fields, minLength = None) : """Creates a fulltext index if it does not already exist, and returns it"""

        data = {
            "type" : "fulltext",
            "fields" : fields,
        }
        if minLength is not None :
            data["minLength"] = minLength

        ind = Index(self, creationData = data)
        self.indexes["fulltext"][ind.infos["id"]] = ind
        return ind