code: func Token(token string) Option {
  	return func(o *Options) error {
  		if o.TokenHandler != nil {
  			return ErrTokenAlreadySet
  		}
  		o.Token = token
  		return nil
  	}
  }
docs: // Token is an Option to set the token to use
  // when a token is not included directly in the URLs
  // and when a token handler is not provided.