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db.collection.aggregate([{"$match":{_id:{$in:[ObjectId("5a934e000102030405000007"),ObjectId("5a934e000102030405000004"),ObjectId("5a934e000102030405000003"),ObjectId("5a934e000102030405000008"),ObjectId("5a934e000102030405000002")]}}},{"$addFields":{"__order":{"$indexOfArray":[[ObjectId("5a934e000102030405000007"),ObjectId("5a934e000102030405000004"),ObjectId("5a934e000102030405000003"),ObjectId("5a934e000102030405000008"),ObjectId("5a934e000102030405000002")],"$_id"]}}},{"$sort":{"__order":1}}])