api.commons.billing.Invoice(Invoice)

{
    "items": [
        {
            "invoice_item_sid": 0,
            "product": "PRODUCT_UNSPECIFIED",
            "amount": 0,
            "date_created": "1s",
            "date_modified": "1s",
            "invoice_id": 0
        }
    ],
    "invoice_id": 0,
    "billing_cycle": "string",
    "create_time": "1s",
    "update_time": "1s"
}