export default class Aggregation { _db: any; _request: any; _stages: any[]; _collectionName: string; constructor(db?: any, collectionName?: any); end(): Promise; unwrap(): any[]; done(): { [x: number]: any; }[]; _pipe(stage: any, param: any): this; addFields(param: any): this; bucket(param: any): this; bucketAuto(param: any): this; count(param: any): this; geoNear(param: any): this; group(param: any): this; limit(param: any): this; match(param: any): this; project(param: any): this; lookup(param: any): this; replaceRoot(param: any): this; sample(param: any): this; skip(param: any): this; sort(param: any): this; sortByCount(param: any): this; unwind(param: any): this; }