'The list of versions is dependent on the context.'

def _get_versions_list(self, context):

    versions = {}
    if ('v2.0' in _VERSIONS):
        versions['v2.0'] = {'id': 'v2.0', 'status': 'deprecated', 'updated': '2016-08-04T00:00:00Z', 'links': [{'rel': 'self', 'href': self._get_identity_url(context, 'v2.0')}, {'rel': 'describedby', 'type': 'text/html', 'href': 'https://docs.openstack.org/'}], 'media-types': [{'base': 'application/json', 'type': (MEDIA_TYPE_JSON % 'v2.0')}]}
    if ('v3' in _VERSIONS):
        versions['v3'] = {'id': 'v3.8', 'status': 'stable', 'updated': '2017-02-22T00:00:00Z', 'links': [{'rel': 'self', 'href': self._get_identity_url(context, 'v3')}], 'media-types': [{'base': 'application/json', 'type': (MEDIA_TYPE_JSON % 'v3')}]}
    return versions
