How to use the @aws-cdk/aws-iam.CfnAccessKey function in @aws-cdk/aws-iam

statements: [
        new PolicyStatement({
          actions: ["rds-data:*"],
          resources: [
            `arn:aws:rds:${this.region}:${this.account}:cluster:${DB_CLUSTER_ID}*`,
            `arn:aws:rds:${this.region}:${this.account}:cluster:${DB_CLUSTER_ID}2*`
          ]
        }),
        new PolicyStatement({
          actions: ["secretsmanager:*"],
          resources: [`${secret.ref}*`, `${secret2.ref}*`]
        })
      ]
    });
    user.attachInlinePolicy(policy);
    const key = new CfnAccessKey(this, "TestUserKey", {
      userName: user.userName
    });
    new CfnOutput(this, "AASAUserAccessKeyId", {
      value: key.ref
    });
    new CfnOutput(this, "AASAUserSecretAccessKey", {
      value: key.attrSecretAccessKey
    });
  }
}