code: def save_json(val, pretty=False, sort=True, encoder=None):
      if encoder is None:
          encoder = DateTimeEncoder
      if pretty:
          data = json.dumps(
              val,
              indent=4,
              separators=(',', ': '),
              sort_keys=sort,
              cls=encoder
          )
      else:
          data = json.dumps(
              val,
              separators=(',', ':'),
              sort_keys=sort,
              cls=encoder
          )
      if not sys.version_info > (3, 0) and isinstance(data, str):
          data = data.decode("utf-8")
      return data