code: def unregister(self, document):
          
          if document not in self.documents.keys():
              self.log.warning("Can not unregister document %s" % document)
          else:
              del (self.documents[document])
              self.__log.debug("Document %s got unregistered" % document)
docs: Unregisters an existing document, so that this document is no longer available.
  
          This function is mainly used during plugin deactivation.
  
          :param document: Name of the document