static <T, R> ContextAwareFunction<T, R> of(RequestContext context, Function<T, R> function) {
        return new DefaultContextAwareFunction<>(context, function);
    }
Returns a new {@link ContextAwareFuture} that sets the specified {@link RequestContext}
before executing an underlying {@link Function}.
core/src/main/java/com/linecorp/armeria/common/ContextAwareFunction.java