code: func GetMaxAge(reqCtx *fasthttp.RequestCtx) entry.LifeChanger {
  	return func() time.Duration {
  		cacheControlHeader := string(reqCtx.Request.Header.Peek("Cache-Control"))
  		// headerCacheDur returns the seconds
  		headerCacheDur := entry.ParseMaxAge(cacheControlHeader)
  		return time.Duration(headerCacheDur) * time.Second
  	}
  }
docs: // GetMaxAge parses the "Cache-Control" header
  // and returns a LifeChanger which can be passed
  // to the response's Reset