src/vs/workbench/contrib/notebook/common/services/notebookSimpleWorker.ts/MirrorCell/constructor
class MirrorCell:	constructor(
		readonly handle: number,
		private _source: string | string[],
		public language: string,
		public cellKind: CellKind,
		public outputs: IOutputDto[],
		public metadata?: NotebookCellMetadata,
		public internalMetadata?: NotebookCellInternalMetadata,

	) { }