code: public CommandOption findShort(String argument) {
  
  		Assert.notNullOrEmptyTrimmed(argument, "Missing short name!");
  
  		Optional<CommandOption> found = options.stream().filter(o -> o.isShort(argument)).findFirst();
  		return found.orElse(null);
  	}
docs: Find option by short name
  
  @param argument short name
  @return found option or null if none found