code: function initialize() {
      var creditcard;
      // [square] @import "creditcard/index.js"
      this.lib = creditcard;
  
      //
      // Create references to elements.
      //
      this.number = this.$('input[name="full_number"]');
      this.cvv = this.$('input[name="cvv"]');
      this.year = this.$('select[name="expiration_year"]');
      this.month = this.$('select[name="expiration_month"]');
      this.card = this.$('.card');
  
      //
      // Is validation required?
      //
      this.validate = !!this.$el.get('validate');
    }
docs: Import the credit card library and store a reference in lib.
  
  @api private