code: def save(self, filename, incl_uniqueid=False, compact=False):
          
          filename = os.path.expanduser(filename)
          f = open(filename, 'w')
          if compact:
              if _can_ujson:
                  ujson.dump(self.to_json(incl_uniqueid=incl_uniqueid), f,
                             sort_keys=False, indent=0)
              else:
                  logger.warning("for faster compact saving, install ujson")
                  json.dump(self.to_json(incl_uniqueid=incl_uniqueid), f,
                            sort_keys=False, indent=0)
          else:
              json.dump(self.to_json(incl_uniqueid=incl_uniqueid), f,
                        sort_keys=True, indent=0, separators=(',', ': '))
          f.close()
  
          return filename
docs: Save the ParameterSet to a JSON-formatted ASCII file
  
          :parameter str filename: relative or fullpath to the file
          :parameter bool incl_uniqueid: whether to including uniqueids in the
              file (only needed if its necessary to maintain the uniqueids when
              reloading)
          :parameter bool compact: whether to use compact file-formatting (maybe
              be quicker to save/load, but not as easily readable)
          :return: filename
          :rtype: str