ReadonlyactionOptional ReadonlyexternalAn external Tax Rate can be set if the Cart has the External TaxMode.
Optional ReadonlyshippingValue to set. If empty, any existing value is removed.
[InvalidOperation](ctp:api:type:InvalidOperationError) error is returned in one of the following cases:
1. If the referenced Shipping Method has a predicate that does not match the Cart.
2. If the referenced Shipping Method is not active.
3. If the referenced Shipping Method is associated with a Store that is different from the Cart's Store.
4. If the referenced Shipping Method is associated with a Store and the Cart is not associated with any Store.
To set the Cart's Shipping Method the Cart must have the
SingleShippingMode and ashippingAddress.