In keeping with [CCP's recommended practices](https://developers.eveonline.com/blog/article/breaking-changes-and-you), this allows initialization of swagger clients for specific API versions. Simply pass the `version` kwarg to the client factory. Note that not all resources will be available on versioned clients: only resources with an available version matching the one specified will be available on the returned client. Multiple clients will be needed to access resources of different versions.