How to use the @storefront-api/lib/taxcalc.checkIfTaxWithUserGroupIsActive function in @storefront-api/lib

client.search(esQuery).then((result) => { // we're always trying to populate cache - when online
          inst._taxClasses = es.getHits(result).map(el => { return el._source })
          for (let item of productList) {
            const isActive = checkIfTaxWithUserGroupIsActive(inst._storeConfigTax)
            if (isActive) {
              groupId = getUserGroupIdToUse(inst._userGroupId, inst._storeConfigTax)
            } else {
              groupId = null
            }

            inst.taxFor(item._source, groupId)
          }

          resolve(productList)
        }).catch(err => {
          reject(err)

client.search(esQuery).then((body) => { // we're always trying to populate cache - when online
          inst._taxClasses = es.getHits(body).map(el => { return el._source })
          for (let item of productList) {
            const isActive = checkIfTaxWithUserGroupIsActive(inst._storeConfigTax)
            if (isActive) {
              groupId = getUserGroupIdToUse(inst._userGroupId, inst._storeConfigTax)
            } else {
              groupId = null
            }

            inst.taxFor(item._source, groupId)
          }

          resolve(productList)
        }).catch(err => {
          reject(err)

taxFor (product, groupId) {
    return calculateProductTax({
      product,
      taxClasses: this._taxClasses,
      taxCountry: this._taxCountry,
      taxRegion: this._taxRegion,
      sourcePriceInclTax: this._sourcePriceInclTax,
      deprecatedPriceFieldsSupport: this._deprecatedPriceFieldsSupport,
      finalPriceInclTax: this._finalPriceInclTax,
      userGroupId: groupId,
      isTaxWithUserGroupIsActive: checkIfTaxWithUserGroupIsActive(this._storeConfigTax) && typeof groupId === 'number'
    })
  }

taxFor (product, groupId) {
    return calculateProductTax({
      product,
      taxClasses: this._taxClasses,
      taxCountry: this._taxCountry,
      taxRegion: this._taxRegion,
      sourcePriceInclTax: this._sourcePriceInclTax,
      deprecatedPriceFieldsSupport: this._deprecatedPriceFieldsSupport,
      finalPriceInclTax: this._finalPriceInclTax,
      userGroupId: groupId,
      isTaxWithUserGroupIsActive: checkIfTaxWithUserGroupIsActive(this._storeConfigTax) && typeof groupId === 'number'
    })
  }