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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 contains(self, data):
 """ Check if an item has been added to the bloomfilter. :param bytes data: a bytestring representing the item to check. :returns: a boolean indicating whether or not the item is present in the bloomfilter. False-positives are possible, but a negative return value is definitive. """

        bfo = BitFieldOperation(self.database, self.key)
        for bit_index in self._get_seeds(data):
            bfo.get('u1', bit_index)
        return all(bfo.execute())