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_DescribeDeviceEc2Instances.go
    path of file: ./repos/aws-sdk-go-v2/service/snowdevicemanagement
    
    the code of the file until where you have to start completion: // Code generated by smithy-go-codegen DO NOT EDIT.

package snowdevicemanagement

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

// Checks the current state of the Amazon EC2 instances. The output is similar to
// describeDevice , but the results are sourced from the device cache in the Amazon
// Web Services Cloud and include a subset of the available fields.
func (c *Client) DescribeDeviceEc2Instances(ctx context.Context, params *DescribeDeviceEc2InstancesInput, optFns ...func(*Options)) (*DescribeDeviceEc2InstancesOutput, error) {
	if params == nil {
		params = &DescribeDeviceEc2InstancesInput{}
	}

	result, metadata, err := c.invokeOperation(ctx, "DescribeDeviceEc2Instances", params, optFns, c.addOperationDescribeDeviceEc2InstancesMiddlewares)
	if err != nil {
		return nil, err
	}

	out := result.(*DescribeDeviceEc2InstancesOutput)
	out.ResultMetadata = metadata
	return out, nil
}

type DescribeDeviceEc2InstancesInput struct {

	// A list of instance IDs associated with the managed device.
	//
	// This member is required.
	InstanceIds []string

	// The ID of the managed device.
	//
	// This member is required.
	ManagedDeviceId *string

	noSmithyDocumentSerde
}

type DescribeDeviceEc2InstancesOutput struct {

	// A list of structures containing information about each instance.
	Instances []types.InstanceSummary

	// Metadata pertaining to the operation's result.
	ResultMetadata middleware.Metadata

	noSmithyDocumentSerde
}

func (c *Client) addOperationDescribeDeviceEc2InstancesMiddlewares(stack *middleware.Stack, options Options) (
    
func (c *Client) addOperationDescribeDeviceEc2InstancesMiddlewares(stack *middleware.Stack, options Options) (err error) {
	if err := stack.Serialize.Add(&setOperationInputMiddleware{}, middleware.After); err != nil {
		return err
	}
	err = stack.Serialize.Add(&awsRestjson1_serializeOpDescribeDeviceEc2Instances{}, middleware.After)
	if err != nil {
		return err
	}
	err = stack.Deserialize.Add(&awsRestjson1_deserializeOpDescribeDeviceEc2Instances{}, middleware.After)
	if err != nil {
		return err
	}
	if err := addProtocolFinalizerMiddlewares(stack, options, "DescribeDeviceEc2Instances"); 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 = addOpDescribeDeviceEc2InstancesValidationMiddleware(stack); err != nil {
		return err
	}
	if err = stack.Initialize.Add(newServiceMetadataMiddleware_opDescribeDeviceEc2Instances(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
}