docs: public Group lookupGroup(String url) throws FlickrException {
          Map<String, Object> parameters = new HashMap<String, Object>();
          parameters.put("method", METHOD_LOOKUP_GROUP);
  
          parameters.put("url", url);
  
          Response response = transport.get(transport.getPath(), parameters, apiKey, sharedSecret);
          if (response.isError()) {
              throw new FlickrException(response.getErrorCode(), response.getErrorMessage());
          }
  
          Group group = new Group();
          Element payload = response.getPayload();
          Element groupnameElement = (Element) payload.getElementsByTagName("groupname").item(0);
          group.setId(payload.getAttribute("id"));
          group.setName(((Text) groupnameElement.getFirstChild()).getData());
          return group;
      }