code: public List<String> getVersions(String userAgent, String xUserAgent) throws ApiException {
          ApiResponse<List<String>> resp = getVersionsWithHttpInfo(userAgent, xUserAgent);
          return resp.getData();
      }
docs: List versions List all endpoint versions
  
  @param userAgent
  Client identifier, takes precedence over headers (optional)
  @param xUserAgent
  Client identifier, takes precedence over User-Agent (optional)
  @return List&lt;String&gt;
  @throws ApiException
  If fail to call the API, e.g. server error or cannot
  deserialize the response body