How to use the @fullcalendar/core.parseDragMeta function in @fullcalendar/core

function getDragMetaFromEl(el: HTMLElement): DragMeta {
  let str = getEmbeddedElData(el, 'event')
  let obj = str ?
    JSON.parse(str) :
    { create: false } // if no embedded data, assume no event creation

  return parseDragMeta(obj)
}

function getDragMetaFromEl(el) {
    var str = getEmbeddedElData(el, 'event');
    var obj = str ?
        JSON.parse(str) :
        { create: false }; // if no embedded data, assume no event creation
    return parseDragMeta(obj);
}
config.dataAttrPrefix = '';

ExternalElementDragging.prototype.buildDragMeta = function (subjectEl) {
        if (typeof this.suppliedDragMeta === 'object') {
            return parseDragMeta(this.suppliedDragMeta);
        }
        else if (typeof this.suppliedDragMeta === 'function') {
            return parseDragMeta(this.suppliedDragMeta(subjectEl));
        }
        else {
            return getDragMetaFromEl(subjectEl);
        }
    };
    ExternalElementDragging.prototype.displayDrag = function (nextCalendar, state) {

buildDragMeta(subjectEl: HTMLElement) {
    if (typeof this.suppliedDragMeta === 'object') {
      return parseDragMeta(this.suppliedDragMeta)
    } else if (typeof this.suppliedDragMeta === 'function') {
      return parseDragMeta(this.suppliedDragMeta(subjectEl))
    } else {
      return getDragMetaFromEl(subjectEl)
    }
  }

buildDragMeta(subjectEl: HTMLElement) {
    if (typeof this.suppliedDragMeta === 'object') {
      return parseDragMeta(this.suppliedDragMeta)
    } else if (typeof this.suppliedDragMeta === 'function') {
      return parseDragMeta(this.suppliedDragMeta(subjectEl))
    } else {
      return getDragMetaFromEl(subjectEl)
    }
  }

ExternalElementDragging.prototype.buildDragMeta = function (subjectEl) {
        if (typeof this.suppliedDragMeta === 'object') {
            return parseDragMeta(this.suppliedDragMeta);
        }
        else if (typeof this.suppliedDragMeta === 'function') {
            return parseDragMeta(this.suppliedDragMeta(subjectEl));
        }
        else {
            return getDragMetaFromEl(subjectEl);
        }
    };
    ExternalElementDragging.prototype.displayDrag = function (nextCalendar, state) {