如何通过UTC偏移量加载位置

I want to load location via UTC offset, e.g.

func main() {
    L, err := time.LoadLocation("UTC+8")
    if err != nil {
        panic(err)
    }
    fmt.Println(L)
}

The code panics: panic: unknown time zone UTC+8

How can I get the location object by UTC offset (NOT local nor UTC, but another location), without having to specify it in IANA Time Zone format, such as "America/New_York"

My purpose is simple: I have a web server running in a fixed location, which I can get the local time easily. Now I want to do time calculation based on the location of visitor (which is sent over by a url parameter, e.g. http://myserver.com/do_something?timezone=-8).

I found it:

time.FixedZone(name string, offset int)

This will create a Location with given name (which is not important) and the offset.