code: def remove(self, cond=None, doc_ids=None, eids=None):
          
          doc_ids = _get_doc_ids(doc_ids, eids)
  
          if cond is None and doc_ids is None:
              raise RuntimeError('Use purge() to remove all documents')
  
          return self.process_elements(
              lambda data, doc_id: data.pop(doc_id),
              cond, doc_ids
          )
docs: Remove all matching documents.
  
          :param cond: the condition to check against
          :type cond: query
          :param doc_ids: a list of document IDs
          :type doc_ids: list
          :returns: a list containing the removed document's ID