List Countries
Returns a list of **all** countries and, if applicable, their states. The response includes the name and code of each returned element and the id of each country.
**NOTE:** Due to the size of the list returned, the results should be cached for continued use, if possible.
Equivalent Storefront GraphQL API Query: `countries`. For more information, see the [GraphQL Playground](https://api-b2b.bigcommerce.com/graphql/playground).