How to use the @iabtcf/core.TCString.encode function in @iabtcf/core

private update(): void {

    try {

      this.encodedTCString = TCString.encode(this.tcModel);

    } catch (err) {

      this.encodedTCString = 'ERROR... ' + err;

    }

  }

for (const id in specialFeatures) {

        if (specialFeatures.hasOwnProperty(id)) {

          const specialFeature: Feature = specialFeatures[id];
          this.specialFeatures_.push({
            text: specialFeature.name,
            value: id,
          });

        }

      }

      this.encodedTCString = TCString.encode(this.tcModel);

    });

public constructor(tcModel: TCModel, eventStatus: EventStatus, _vendorIds?: number[]) {

    super();

    const vendorIds: string[] = this.getVendorIds(tcModel, _vendorIds);
    const purposeIds: string[] = Object.keys(tcModel.gvl.purposes);
    const specialFeatureIds: string[] = Object.keys(tcModel.gvl.specialFeatures);

    this.tcString = TCString.encode(tcModel);
    this.eventStatus = eventStatus;
    this.isServiceSpecific = tcModel.isServiceSpecific;
    this.useNonStandardStacks = tcModel.useNonStandardStacks;
    this.purposeOneTreatment = tcModel.purposeOneTreatment;
    this.publisherCC = tcModel.publisherCountryCode;

    this.outOfBand = {
      allowedVendors: createBooleanVector(tcModel.vendorsAllowed),
      discloseVendors: createBooleanVector(tcModel.vendorsDisclosed),
    };

    this.purpose = {

      consents: this.createVectorField(purposeIds, tcModel.purposeConsents),
      legitimateInterests: this.createVectorField(purposeIds, tcModel.purposeLegitimateInterest),