Update weight watcher codes

lib/nas_201_api/api_301.py

@@ -75,11 +75,13 @@ class NASBench301API(NASBenchMetaAPI):
     self.meta_archs = copy.deepcopy( file_path_or_dict['meta_archs'] )
     # This is a dict mapping each architecture to a dict, where the key is #epochs and the value is ArchResults
     self.arch2infos_dict = OrderedDict()
+    self._avaliable_hps = set()
     for xkey in sorted(list(file_path_or_dict['arch2infos'].keys())):
       all_infos = file_path_or_dict['arch2infos'][xkey]
       hp2archres = OrderedDict()
       for hp_key, results in all_infos.items():
         hp2archres[hp_key] = ArchResults.create_from_state_dict(results)
+        self._avaliable_hps.add(hp_key)  # save the avaliable hyper-parameter
       self.arch2infos_dict[xkey] = hp2archres
     self.evaluated_indexes = sorted(list(file_path_or_dict['evaluated_indexes']))
     self.archstr2index = {}