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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 get_ceph_pool_sample(self, sentry_unit, pool_id=0):
 """Take a sample of attributes of a ceph pool, returning ceph pool name, object count and disk space used for the specified pool ID number. :param sentry_unit: Pointer to amulet sentry instance (juju unit) :param pool_id: Ceph pool ID :returns: List of pool name, object count, kb disk space used """

        df = self.get_ceph_df(sentry_unit)
        for pool in df['pools']:
            if pool['id'] == pool_id:
                pool_name = pool['name']
                obj_count = pool['stats']['objects']
                kb_used = pool['stats']['kb_used']

        self.log.debug('Ceph {} pool (ID {}): {} objects, '
                       '{} kb used'.format(pool_name, pool_id,
                                           obj_count, kb_used))
        return pool_name, obj_count, kb_used