How to use the @elastic/apm-rum-core.createServiceFactory function in @elastic/apm-rum-core

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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
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 */

import bootstrap from './bootstrap'
import { createServiceFactory } from '@elastic/apm-rum-core'
import ApmBase from './apm-base'

const enabled = bootstrap()
const serviceFactory = createServiceFactory()
const apmBase = new ApmBase(serviceFactory, !enabled)

if (typeof window !== 'undefined') {
  window.elasticApm = apmBase
}

const init = apmBase.init.bind(apmBase)

export default init
export { init, apmBase, ApmBase, apmBase as apm }