How to use the clappr.PlayerError.Levels function in clappr

_onError (err) {
    const error = {
      shakaError: err,
      videoError: this.el.error
    }

    let { category, code, severity } = error.shakaError.detail || error.shakaError

    if (error.videoError || !code && !category) return super._onError()

    const isCritical = severity === shaka.util.Error.Severity.CRITICAL
    const errorData = {
      code: `${category}_${code}`,
      description: `Category: ${category}, code: ${code}, severity: ${severity}`,
      level: isCritical ? PlayerError.Levels.FATAL : PlayerError.Levels.WARN,
      raw: err
    }
    const formattedError = this.createError(errorData)
    Log.error('Shaka error event:', formattedError)
    this.trigger(Events.PLAYBACK_ERROR, formattedError)
  }