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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 _hash(self):
 """Return a hash for the current query. This hash is _not_ a unique representation of the dataset! """

        dump = dumps(self.query, sort_keys=True)
        if isinstance(dump, str):
            dump = dump.encode('utf-8')
        return md5(dump).hexdigest()