How to use the @opentelemetry/core.otperformance.getEntriesByType function in @opentelemetry/core

private _getEntries() {
    const entries: PerformanceEntries = {};
    const performanceNavigationTiming = (otperformance.getEntriesByType(
      'navigation'
    )[0] as unknown) as PerformanceEntries;

    if (performanceNavigationTiming) {
      const keys = Object.values(PTN);
      keys.forEach((key: string) => {
        if (hasKey(performanceNavigationTiming, key)) {
          const value = performanceNavigationTiming[key];
          if (typeof value === 'number' && value > 0) {
            entries[key] = value;
          }
        }
      });
    } else {
      // // fallback to previous version
      const perf: typeof otperformance & PerformanceLegacy = otperformance;

private _addResourcesSpans(rootSpan: Span): void {
    const resources: PerformanceResourceTiming[] = otperformance.getEntriesByType(
      'resource'
    ) as PerformanceResourceTiming[];
    if (resources) {
      resources.forEach(resource => {
        this._initResourceSpan(resource, {
          parent: rootSpan,
        });
      });
    }
  }