code: public static boolean deletePublicKeyNode(PepManager pepManager, OpenPgpV4Fingerprint fingerprint)
              throws XMPPException.XMPPErrorException, SmackException.NotConnectedException, InterruptedException,
              SmackException.NoResponseException {
          PubSubManager pm = pepManager.getPepPubSubManager();
          return pm.deleteNode(PEP_NODE_PUBLIC_KEY(fingerprint));
      }
docs: Delete the public key node of the key with fingerprint {@code fingerprint}.
  
  @param pepManager The PEP manager.
  @param fingerprint fingerprint of the key we want to delete
  
  @throws XMPPException.XMPPErrorException in case of an XMPP protocol error.
  @throws SmackException.NotConnectedException if we are not connected.
  @throws InterruptedException if the thread gets interrupted.
  @throws SmackException.NoResponseException if the server doesn't respond.
  @return <code>true</code> if the node existed and was deleted, <code>false</code> if the node did not exist.