Defines the struct for storing a Package, which is then passed along with an origin and destination address for shipping estimates. A description is optional, as it may or may not be used with various carriers. The monetary_value might be required depending on the origin/destination countries of the shipment.

%Shippex.Package{length: 8
                 width: 8,
                 height: 8,
                 weight: 5.5,
                 monetary_value: 100}