docs: def purge_unused(self, pass_count=3):
          """Append an purge model entry to the journal.
  
          This instructs Revit to purge the open model.
  
          Args:
              pass_count (int): number of times to execute the purge.
                                default is 3
          """
          for purge_count in range(0, pass_count):
              self._add_entry(templates.PROJECT_PURGE)