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: resource_container_cluster_migrate.go
    path of file: ./repos/magic-modules/mmv1/third_party/terraform/services/container
    
    the code of the file until where you have to start completion: package container

import (
	"fmt"
	"log"
	"strconv"
	"strings"

	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
	"github.com/hashicorp/terraform-plugin-sdk/v2/terraform"
)

func resourceContainerClusterMigrateState(
	v int, is *terraform.InstanceState, meta interface{}) (*terraform.InstanceState, error) {
	if is.Empty() {
		log.Println("[DEBUG] Empty InstanceState; nothing to migrate.")
		return is, nil
	}

	switch v {
	case 0:
		log.Println("[INFO] Found Container Cluster State v0; migrating to v1")
		return migrateClusterStateV0toV1(is)
	case 1:
		log.Println("[INFO] Found Container Cluster State v1 in legacy migration function; returning as non-op")
		return is, nil
	default:
		return is, fmt.Errorf("Unexpected schema version: %d", v)
	}
}

func migrateClusterStateV0toV1(is *terraform.InstanceState) (*terra
    
func migrateClusterStateV0toV1(is *terraform.InstanceState) (*terraform.InstanceState, error) {
	log.Printf("[DEBUG] Attributes before migration: %#v", is.Attributes)

	newZones := []string{}

	for k, v := range is.Attributes {
		if !strings.HasPrefix(k, "additional_zones.") {
			continue
		}

		if k == "additional_zones.#" {
			continue
		}

		// Key is now of the form additional_zones.%d
		kParts := strings.Split(k, ".")

		// Sanity check: two parts should be there and <N> should be a number
		badFormat := false
		if len(kParts) != 2 {
			badFormat = true
		} else if _, err := strconv.Atoi(kParts[1]); err != nil {
			badFormat = true
		}

		if badFormat {
			return is, fmt.Errorf("migration error: found additional_zones key in unexpected format: %s", k)
		}

		newZones = append(newZones, v)
		delete(is.Attributes, k)
	}

	for _, v := range newZones {
		hash := schema.HashString(v)
		newKey := fmt.Sprintf("additional_zones.%d", hash)
		is.Attributes[newKey] = v
	}

	log.Printf("[DEBUG] Attributes after migration: %#v", is.Attributes)
	return is, nil
}