How to use the @material/form-field/dist/mdc.formField.MDCFormFieldFoundation.strings function in @material/form-field

getDefaultFoundation() {
    this.label_ = this.root_.querySelector(
      MDCFormFieldFoundation.strings.LABEL_SELECTOR
    )
    // prettier-ignore
    return new MDCFormFieldFoundation({
      registerInteractionHandler: (type, handler) => this.label_.addEventListener(type, handler),
      deregisterInteractionHandler: (type, handler) => this.label_.removeEventListener(type, handler),
      activateInputRipple: () => {
        if (this.input_ && this.input_.ripple) {
          this.input_.ripple.activate()
        }
      },
      deactivateInputRipple: () => {
        if (this.input_ && this.input_.ripple) {
          this.input_.ripple.deactivate()
        }
      },
    })