Modifies an existing checkout

{
    "checkout": {
        "completed_at": null,
        "created_at": "2012-10-12T07:05:27-04:00",
        "currency": "USD",
        "presentment_currency": "USD",
        "customer_id": 207119551,
        "customer_locale": "en",
        "device_id": null,
        "discount_code": null,
        "discount_codes": [],
        "email": "bob.norman@mail.example.com",
        "legal_notice_url": null,
        "location_id": null,
        "name": "#862052962",
        "note": "",
        "note_attributes": {
            "custom engraving": "Happy Birthday",
            "colour": "green"
        },
        "order_id": null,
        "order_status_url": null,
        "order": null,
        "payment_due": "398.00",
        "payment_url": "https://app.local/cardserver/sessions",
        "payments": [],
        "phone": null,
        "shopify_payments_account_id": null,
        "privacy_policy_url": null,
        "refund_policy_url": null,
        "requires_shipping": true,
        "reservation_time_left": 0,
        "reservation_time": null,
        "source_identifier": null,
        "source_name": "web",
        "source_url": null,
        "subscription_policy_url": null,
        "subtotal_price": "398.00",
        "shipping_policy_url": null,
        "tax_exempt": false,
        "taxes_included": false,
        "terms_of_sale_url": null,
        "terms_of_service_url": null,
        "token": "exuw7apwoycchjuwtiqg8nytfhphr62a",
        "total_price": "398.00",
        "total_tax": "0.00",
        "total_tip_received": "0.00",
        "total_line_items_price": "398.00",
        "updated_at": "2023-01-03T12:41:57-05:00",
        "user_id": null,
        "web_url": "https://checkout.local/548380009/checkouts/exuw7apwoycchjuwtiqg8nytfhphr62a",
        "total_duties": null,
        "total_additional_fees": null,
        "line_items": [
            {
                "id": "71e61dc0fa94a2fc",
                "key": "71e61dc0fa94a2fc",
                "product_id": 632910392,
                "variant_id": 49148385,
                "sku": "IPOD2008RED",
                "vendor": "Apple",
                "title": "IPod Nano - 8GB",
                "variant_title": "Red",
                "image_url": "https://cdn.shopify.com/s/files/1/0005/4838/0009/products/ipod-nano.png?v=1672766496",
                "taxable": true,
                "requires_shipping": true,
                "gift_card": false,
                "price": "199.00",
                "compare_at_price": null,
                "line_price": "199.00",
                "properties": {},
                "quantity": 1,
                "grams": 200,
                "fulfillment_service": "manual",
                "applied_discounts": [],
                "discount_allocations": [],
                "tax_lines": []
            },
            {
                "id": "d76e2360549fc5e0",
                "key": "d76e2360549fc5e0",
                "product_id": 632910392,
                "variant_id": 808950810,
                "sku": "IPOD2008PINK",
                "vendor": "Apple",
                "title": "IPod Nano - 8GB",
                "variant_title": "Pink",
                "image_url": "https://cdn.shopify.com/s/files/1/0005/4838/0009/products/ipod-nano-2.png?v=1672766496",
                "taxable": true,
                "requires_shipping": true,
                "gift_card": false,
                "price": "199.00",
                "compare_at_price": null,
                "line_price": "199.00",
                "properties": {},
                "quantity": 1,
                "grams": 200,
                "fulfillment_service": "manual",
                "applied_discounts": [],
                "discount_allocations": [],
                "tax_lines": []
            }
        ],
        "gift_cards": [],
        "tax_lines": [],
        "tax_manipulations": [],
        "shipping_line": {
            "handle": "shopify-Free%20Shipping-0.00",
            "price": "0.00",
            "title": "Free Shipping",
            "tax_lines": []
        },
        "shipping_rate": {
            "id": "shopify-Free%20Shipping-0.00",
            "price": "0.00",
            "title": "Free Shipping"
        },
        "shipping_address": {
            "id": 550558813,
            "first_name": "Bob",
            "last_name": "Norman",
            "phone": "+1(502)-459-2181",
            "company": null,
            "address1": "Chestnut Street 92",
            "address2": "",
            "city": "Louisville",
            "province": "Kentucky",
            "province_code": "KY",
            "country": "United States",
            "country_code": "US",
            "zip": "40202"
        },
        "credit_card": null,
        "billing_address": {
            "id": 550558813,
            "first_name": "Bob",
            "last_name": "Norman",
            "phone": "+1(502)-459-2181",
            "company": null,
            "address1": "Chestnut Street 92",
            "address2": "",
            "city": "Louisville",
            "province": "Kentucky",
            "province_code": "KY",
            "country": "United States",
            "country_code": "US",
            "zip": "40202"
        },
        "applied_discount": null,
        "applied_discounts": [],
        "discount_violations": []
    }
}