Version 2.0 has been short-lived and has now been replaced with version 3.0.0

Between version 2.0 and version 3.0, the output for the REST endpoints has changed but any other functionalities are identical.

Please refer to the 1.0 to 3.0 migration guide for more information: https://github.com/Ensembl/ensembl-rest/wiki/1.0-To-3.0-Migration