declare function importTxt(files: FileList | null | undefined): Promise<string | null>;
/**
 * This function only return valid lines, i.e: with content after trimming.
 */
declare function importTxtInLines(files: FileList | null | undefined): Promise<string[] | null>;
export declare const ImportUtil: Readonly<{
    importTxt: typeof importTxt;
    importTxtInLines: typeof importTxtInLines;
}>;
export {};