function groupBy(items: Record<string, any>[], key: string): Record<string, Record<string, any>[]> {
  if(items.length <= 0) return {};


const tester = items.map(e => e[key]);
const tester1 = [...new Set(tester)];
const tester2 = {};

tester1.forEach( e => {
  const filt = items.filter( item => item[key] === e);
  tester2[e] = filt;
})

  return tester2;
}

// No modificar: necesario para evaluar el resultado.
export { groupBy };