const stringUtils = {
  capitalize: (s: string) => s.charAt(0).toUpperCase() + s.slice(1),
};

// Desestructura capitalize de stringUtils y úsala en formatName
export function formatName(firstName: string, lastName: string): string {
  // Tu código aquí
  const {capitalize} = stringUtils;


  return capitalize(firstName) + " " + capitalize(lastName);
}