Refining TypeScript Schema for SQS Message Attributes

const Attributes = Schema.Literal('tenantId', 'sesssionId', 'status')
type Attributes = Schema.Schema.Type<typeof Attributes>

export const SqsMessageAttributes = Schema.Struct({
    DataType: Schema.Literal('String'),
    StringValue: Schema.String,
})
export type SqsMessageAttributes = Schema.Schema.Type<typeof SqsMessageAttributes>
export class SqsMessage extends Schema.Class<SqsMessage>('SqsMessage')({
    MessageBody: Schema.String,
    QueueUrl: Schema.String,
    MessageAttributes: Schema.NullOr(Schema.Record({ key: Attributes, value: SqsMessageAttributes })),
}) {}