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: bingads_test.go
    path of file: ./repos/rudder-server/router/batchrouter/asyncdestinationmanager/bing-ads
    
    the code of the file until where you have to start completion: package bingads

import (
	stdjson "encoding/json"
	"fmt"
	"io"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"sync"

	"github.com/golang/mock/gomock"
	. "github.com/onsi/ginkgo/v2"
	. "github.com/onsi/gomega"

	bingads_sdk "github.com/rudderlabs/bing-ads-go-sdk/bingads"
	"github.com/rudderlabs/rudder-go-kit/bytesize"
	"gi
    
func DuplicateFile(sourcePath, destinationPath string) error {
	// Open the source file
	sourceFile, err := os.Open(sourcePath)
	if err != nil {
		return fmt.Errorf("failed to open source file: %v", err)
	}
	defer sourceFile.Close()

	// Create the destination file
	destinationFile, err := os.Create(destinationPath)
	if err != nil {
		return fmt.Errorf("failed to create destination file: %v", err)
	}
	defer destinationFile.Close()

	// Copy the contents of the source file to the destination file
	_, err = io.Copy(destinationFile, sourceFile)
	if err != nil {
		return fmt.Errorf("failed to copy file contents: %v", err)
	}

	return nil
}