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: api_op_UpdatePackage.go
    path of file: ./repos/aws-sdk-go-v2/service/elasticsearchservice
    
    the code of the file until where you have to start completion: // Code generated by smithy-go-codegen DO NOT EDIT.

package elasticsearchservice

import (
	"context"
	"fmt"
	awsmiddleware "github.com/aws/aws-sdk-go-v2/aws/middleware"
	"github.com/aws/aws-sdk-go-v2/service/elasticsearchservice/types"
	"github.com/aws/smithy-go/middleware"
	smithyhttp "github.com/aws/smithy-go/transport/http"
)

// Updates a package for use with Amazon ES domains.
func (c *Client) UpdatePackage(ctx context.Context, params *UpdatePackageInput, optFns ...func(*Options)) (*UpdatePackageOutput, error) {
	if params == nil {
		params = &UpdatePackageInput{}
	}

	result, metadata, err := c.invokeOperation(ctx, "UpdatePackage", params, optFns, c.addOperationUpdatePackageMiddlewares)
	if err != nil {
		return nil, err
	}

	out := result.(*UpdatePackageOutput)
	out.ResultMetadata = metadata
	return out, nil
}

// Container for request parameters to UpdatePackage operation.
type UpdatePackageInput struct {

	// Unique identifier for the package.
	//
	// This member is required.
	PackageID *string

	// The S3 location for importing the package specified as S3BucketName and S3Key
	//
	// This member is required.
	PackageSource *types.PackageSource

	// An info message for the new version which will be shown as part of
	// GetPackageVersionHistoryResponse .
	CommitMessage *string

	// New description of the package.
	PackageDescription *string

	noSmithyDocumentSerde
}

// Container for response returned by UpdatePacka
    
func (c *Client) addOperationUpdatePackageMiddlewares(stack *middleware.Stack, options Options) (err error) {
	if err := stack.Serialize.Add(&setOperationInputMiddleware{}, middleware.After); err != nil {
		return err
	}
	err = stack.Serialize.Add(&awsRestjson1_serializeOpUpdatePackage{}, middleware.After)
	if err != nil {
		return err
	}
	err = stack.Deserialize.Add(&awsRestjson1_deserializeOpUpdatePackage{}, middleware.After)
	if err != nil {
		return err
	}
	if err := addProtocolFinalizerMiddlewares(stack, options, "UpdatePackage"); err != nil {
		return fmt.Errorf("add protocol finalizers: %v", err)
	}

	if err = addlegacyEndpointContextSetter(stack, options); err != nil {
		return err
	}
	if err = addSetLoggerMiddleware(stack, options); err != nil {
		return err
	}
	if err = addClientRequestID(stack); err != nil {
		return err
	}
	if err = addComputeContentLength(stack); err != nil {
		return err
	}
	if err = addResolveEndpointMiddleware(stack, options); err != nil {
		return err
	}
	if err = addComputePayloadSHA256(stack); err != nil {
		return err
	}
	if err = addRetry(stack, options); err != nil {
		return err
	}
	if err = addRawResponseToMetadata(stack); err != nil {
		return err
	}
	if err = addRecordResponseTiming(stack); err != nil {
		return err
	}
	if err = addClientUserAgent(stack, options); err != nil {
		return err
	}
	if err = smithyhttp.AddErrorCloseResponseBodyMiddleware(stack); err != nil {
		return err
	}
	if err = smithyhttp.AddCloseResponseBodyMiddleware(stack); err != nil {
		return err
	}
	if err = addSetLegacyContextSigningOptionsMiddleware(stack); err != nil {
		return err
	}
	if err = addOpUpdatePackageValidationMiddleware(stack); err != nil {
		return err
	}
	if err = stack.Initialize.Add(newServiceMetadataMiddleware_opUpdatePackage(options.Region), middleware.Before); err != nil {
		return err
	}
	if err = addRecursionDetection(stack); err != nil {
		return err
	}
	if err = addRequestIDRetrieverMiddleware(stack); err != nil {
		return err
	}
	if err = addResponseErrorMiddleware(stack); err != nil {
		return err
	}
	if err = addRequestResponseLogging(stack, options); err != nil {
		return err
	}
	if err = addDisableHTTPSMiddleware(stack, options); err != nil {
		return err
	}
	return nil
}