code: def load_presets(self, presets_path=None):
          
          presets_path = presets_path or self.presets_path
          if not os.path.exists(presets_path):
              return
          for preset_path in os.listdir(presets_path):
              preset_path = os.path.join(presets_path, preset_path)
  
              try:
                  preset_data = json.load(open(preset_path))
              except ValueError:
                  continue
  
              for preset in preset_data.keys():
                  pd = PresetDefaults(preset, opts=SoSOptions())
                  data = preset_data[preset]
                  pd.desc = data[DESC] if DESC in data else ""
                  pd.note = data[NOTE] if NOTE in data else ""
  
                  if OPTS in data:
                      for arg in _arg_names:
                          if arg in data[OPTS]:
                              setattr(pd.opts, arg, data[OPTS][arg])
                  pd.builtin = False
                  self.presets[preset] = pd
docs: Load presets from disk.
  
              Read JSON formatted preset data from the specified path,
              or the default location at ``/var/lib/sos/presets``.
  
              :param presets_path: a directory containing JSON presets.