You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: main.go
    path of file: ./repos/asynq/tools/metrics_exporter
    
    the code of the file until where you have to start completion: package main

import (
	"flag"
	"fmt"
	"log"
	"net/http"

	"github.com/hibiken/asynq"
	"github.com/hibiken/asynq/x/metrics"
	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/client_golang/prometheus/collectors"
	"gith
    
func main() {
	flag.Parse()
	// Using NewPedanticRegistry here to test the implementation of Collectors and Metrics.
	reg := prometheus.NewPedanticRegistry()

	inspector := asynq.NewInspector(asynq.RedisClientOpt{
		Addr:     flagRedisAddr,
		DB:       flagRedisDB,
		Password: flagRedisPassword,
		Username: flagRedisUsername,
	})

	reg.MustRegister(
		metrics.NewQueueMetricsCollector(inspector),
		// Add the standard process and go metrics to the registry
		collectors.NewProcessCollector(collectors.ProcessCollectorOpts{}),
		collectors.NewGoCollector(),
	)

	http.Handle("/metrics", promhttp.HandlerFor(reg, promhttp.HandlerOpts{}))
	log.Printf("exporter server is listening on port: %d\n", flagPort)
	log.Fatal(http.ListenAndServe(fmt.Sprintf(":%d", flagPort), nil))
}