docs: private static OmemoBundleElement fetchBundle(XMPPConnection connection,
                                                    OmemoDevice contactsDevice)
              throws SmackException.NotConnectedException, InterruptedException, SmackException.NoResponseException,
              XMPPException.XMPPErrorException, PubSubException.NotALeafNodeException,
              PubSubException.NotAPubSubNodeException {
  
          PubSubManager pm = PubSubManager.getInstanceFor(connection, contactsDevice.getJid());
          LeafNode node = pm.getLeafNode(contactsDevice.getBundleNodeName());
  
          if (node == null) {
              return null;
          }
  
          List<PayloadItem<OmemoBundleElement>> bundleItems = node.getItems();
          if (bundleItems.isEmpty()) {
              return null;
          }
  
          return bundleItems.get(bundleItems.size() - 1).getPayload();
      }