`Contact` is a representation of OpenAPI v2 specification's Contact object.

`ExternalDocumentation` is a representation of OpenAPI v2 specification's ExternalDocumentation object.

`Info` is a representation of OpenAPI v2 specification's Info object.

`JSONSchema` represents properties from JSON Schema taken, and as used, in the OpenAPI v2 spec.

`Operation` is a representation of OpenAPI v2 specification's Operation object.

`Schema` is a representation of OpenAPI v2 specification's Schema object.

`Swagger` is a representation of OpenAPI v2 specification's Swagger object.

`Tag` is a representation of OpenAPI v2 specification's Tag object.