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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 cleanup_defenses(self):
 """Cleans up all data about defense work in current round."""

    print_header('CLEANING UP DEFENSES DATA')
    work_ancestor_key = self.datastore_client.key('WorkType', 'AllDefenses')
    keys_to_delete = [
        e.key
        for e in self.datastore_client.query_fetch(kind=u'ClassificationBatch')
    ] + [
        e.key
        for e in self.datastore_client.query_fetch(kind=u'Work',
                                                   ancestor=work_ancestor_key)
    ]
    self._cleanup_keys_with_confirmation(keys_to_delete)