code: func FilterActiveReplicaSets(replicaSets []*apps.ReplicaSet) []*apps.ReplicaSet {
  	activeFilter := func(rs *apps.ReplicaSet) bool {
  		return rs != nil && *(rs.Spec.Replicas) > 0
  	}
  	return FilterReplicaSets(replicaSets, activeFilter)
  }
docs: // FilterActiveReplicaSets returns replica sets that have (or at least ought to have) pods.