docs: def add_doc(self, doc, index_update=True, label_guesser_update=True):
          """
          Add a document to the index
          """
          logger.info("Indexing new doc: %s" % doc)
          doc = doc.clone()  # make sure it can be serialized safely
          self.docsearch.index.add_doc(doc, index_update=index_update,
                                       label_guesser_update=label_guesser_update)