src/vs/workbench/api/common/extHostNotebook.ts/ExtHostNotebookController/_registerApiCommands
class ExtHostNotebookController:	private static _registerApiCommands(extHostCommands: ExtHostCommands) {

		const notebookTypeArg = ApiCommandArgument.String.with('notebookType', 'A notebook type');

		const commandDataToNotebook = new ApiCommand(
			'vscode.executeDataToNotebook', '_executeDataToNotebook', 'Invoke notebook serializer',
			[notebookTypeArg, new ApiCommandArgument<Uint8Array, VSBuffer>('data', 'Bytes to convert to data', v => v instanceof Uint8Array, v => VSBuffer.wrap(v))],
			new ApiCommandResult<NotebookDataDto, vscode.NotebookData>('Notebook Data', dto => typeConverters.NotebookData.to(dto))
		);

		const commandNotebookToData = new ApiCommand(
			'vscode.executeNotebookToData', '_executeNotebookToData', 'Invoke notebook serializer',
			[notebookTypeArg, new ApiCommandArgument<vscode.NotebookData, NotebookDataDto>('NotebookData', 'Notebook data to convert to bytes', v => true, v => typeConverters.NotebookData.from(v))],
			new ApiCommandResult<VSBuffer, Uint8Array>('Bytes', dto => dto.buffer)
		);

		extHostCommands.registerApiCommand(commandDataToNotebook);
		extHostCommands.registerApiCommand(commandNotebookToData);
	}