Convert to Python 3: `dict` key iterations

sznqalibs/hoover.py

 
     def __cleanup_data(self):
         """remove hidden data; e.g. what was only there for _check_data"""
-        for key in self.data.keys():
+        for key in self.data:
             if key.startswith("_"):
                 del self.data[key]
 
         are loaded ("DriverClass.settingName", the first discriminating part
         is removed)"""
         if only_own:
-            for ckey in settings.keys():
+            for ckey in settings:
                 driver_class_name, setting_name = ckey.split(".", 2)
                 if self.__class__.__name__ == driver_class_name:
                     self._settings[setting_name] = settings[ckey]
         )
 
     def _computed_stats(self):
-        computed = dict.fromkeys(self.formulas.keys())
+        computed = dict.fromkeys(self.formulas)
         for fname, fml in self.formulas.items():
             try:
                 v = fml(self.generic_stats, self.driver_stats)
             cn = {}
             for affected in self._db.values():
                 for argset in affected:
-                    cn.update(dict.fromkeys(argset.keys()))
+                    cn.update(dict.fromkeys(argset))
                 return sorted(cn.keys())
 
         all_colnames = get_all_colnames()
         names = []
         iterables = []
 
-        keys = self.scheme.keys()
-
-        for key in keys:
+        for key in self.scheme:
             try:
                 iterables.append(self._get_iterable_for(key))
             except KeyError:

tests/test_hoover.py

                 'b': hoover.Cartman.Iterable,
                 'c': a_mark
             }
-            source = dict.fromkeys(scheme.keys(), [])
+            source = dict.fromkeys(scheme, [])
             iter(hoover.Cartman(source, scheme)).next()
 
         self.assertRaises(ValueError, fn)