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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 is_hash_in_index(self, filehash):
 """ Check if there is a document using this file hash """

        filehash = (u"%X" % filehash)
        results = self.__searcher.search(
            whoosh.query.Term('docfilehash', filehash))
        return bool(results)