func WithLetters(letters string) Option {
	return func(gen *Generator) {
		gen.letters = letters
	}
}
// WithLetters is a function option used
// to specify a custom set of letters
WithLetters is a function option used
to specify a custom set of letters
// WithLetters is a function option used // to specify a custom set of letters
func WithLetters(letters string) Option {
	return func(gen *Generator) {
		gen.letters = letters
	}
}
func WithLetters ( letters string ) Option { return func ( gen * Generator ) { gen . letters = letters } }
WithLetters is a function option used
to specify a custom set of letters
WithLetters is a function option used to specify a custom set of letters