将k8s服务账号与AWS IAM角色相关联，并使用AWS SDK for Go在k8s Service中获取assumed role。代码示例如下：

import (
  "os"
  "github.com/aws/aws-sdk-go/aws/session"
  "github.com/aws/aws-sdk-go/aws/credentials"
  "github.com/aws/aws-sdk-go/aws"
  "github.com/aws/aws-sdk-go/service/sts"
)

func main() {
  // 设置AWS会话
  sess, err := session.NewSession(&aws.Config{
    Region:      aws.String("your_aws_region"),
    Credentials: credentials.NewStaticCredentials("your_aws_access_key_id", "your_aws_secret_access_key", "your_aws_session"),
  })

  // 创建STS服务客户端
  svc := sts.New(sess)

  // 检索IAM Role ARN
  roleArn := "arn:aws:iam::123456789012:role/your_role_name"

  // 检索要假定的AWS账号的外部ID
  externalId := "your_external_id"

  // 假定角色
  assumeRoleSAMLInput := &sts.AssumeRoleInput{
    RoleArn:         aws.String(roleArn),
    ExternalId:      aws.String(externalId),
    RoleSessionName: aws.String("your_session_name"),
  }
  assumeRoleResult, err := svc.AssumeRole(assumeRoleInput)
  if err != nil {
    // 处理错误
    os.Exit(1)
  }

  // 打印假想的凭证
  fmt.Println(assumeRoleResult.Credentials)

  // 使用偏好设置会话密钥创建新的会话
  sess = session.Must(session.NewSession(&aws.Config{
    Region: aws.String("your_aws_region"),
    Credentials: credentials.NewStaticCredentials(
      *assumeRoleResult.Credentials.AccessKeyId,
      *assumeRoleResult.Credentials.SecretAccessKey,
      *assumeRoleResult.Credentials.SessionToken,
    ),
  }))
}