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: ec2_describe_security_groups.go
    path of file: ./repos/aws-doc-sdk-examples/go/example_code/ec2
    
    the code of the file until where you have to start completion: // Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0

package main

import (
	"fmt"
	"os"
	"path/filepath"

	"github.com/aws/aws-sdk-go/aws"
	"github.com/aws/aws-sdk-go/aws/awserr"
	"github.com/aws/aws-sdk-go/aws/session"
	"github.com/aws/aws-sdk-go/service/ec2"
)

// Describes the security groups by IDs that are passed into the CLI. Takes
// a space separated list of group IDs as input.
//
// Usage:
//
//	go run ec2_describe_security_groups.go groupId1 groupId2 ...
func main() {
	if len(os.Args) < 2 {
		exitErrorf("Security Group ID required\nUsage: %s group_id ...",
			filepath.Base(os.Args[0]))
	}
	groupIds := os.Args[1:]

	// Initialize a session in us-west-2 that the SDK will use to load
	// credentials from the shared credentials file ~/.aws/
    
func main() {
	if len(os.Args) < 2 {
		exitErrorf("Security Group ID required\nUsage: %s group_id ...",
			filepath.Base(os.Args[0]))
	}
	groupIds := os.Args[1:]

	// Initialize a session in us-west-2 that the SDK will use to load
	// credentials from the shared credentials file ~/.aws/credentials.
	sess, err := session.NewSession(&aws.Config{
		Region: aws.String("us-west-2")},
	)

	// Create an EC2 service client.
	svc := ec2.New(sess)

	// Retrieve the security group descriptions
	result, err := svc.DescribeSecurityGroups(&ec2.DescribeSecurityGroupsInput{
		GroupIds: aws.StringSlice(groupIds),
	})
	if err != nil {
		if aerr, ok := err.(awserr.Error); ok {
			switch aerr.Code() {
			case "InvalidGroupId.Malformed":
				fallthrough
			case "InvalidGroup.NotFound":
				exitErrorf("%s.", aerr.Message())
			}
		}
		exitErrorf("Unable to get descriptions for security groups, %v", err)
	}

	fmt.Println("Security Group:")
	for _, group := range result.SecurityGroups {
		fmt.Println(group)
	}
}