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: example_ratelimit_test.go
    path of file: ./repos/taskq
    
    the code of the file until where you have to start completion: package taskq_test

import (
	"context"
	"fmt"
	"time"

	"github.com/vmihailenco/taskq/v3"
	"github.com/vmihailenco/taskq/v3/memqueue"
)

type RateLimitError string

func (e RateLimitError) Error() string {
	return string(e)
}


    
func Example_customRateLimit() {
	start := time.Now()
	q := memqueue.NewQueue(&taskq.QueueOptions{
		Name: "test",
	})
	task := taskq.RegisterTask(&taskq.TaskOptions{
		Name: "Example_customRateLimit",
		Handler: func() error {
			fmt.Println("retried in", timeSince(start))
			return RateLimitError("calm down")
		},
		RetryLimit: 2,
		MinBackoff: time.Millisecond,
	})

	ctx := context.Background()
	q.Add(task.WithArgs(ctx))

	// Wait for all messages to be processed.
	_ = q.Close()

	// Output: retried in 0s
	// retried in 3s
}