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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 fulltext(search, lang=Lang.English, ignore_case=True):
 """Full text search. Example:: filters = Text.fulltext("python pymongo_mate") .. note:: This field doesn't need to specify field. """

        return {
            "$text": {
                "$search": search,
                "$language": lang,
                "$caseSensitive": not ignore_case,
                "$diacriticSensitive": False,
            }
        }