Use dict comprehensions instead of dict+zip

Dict comprehensions are more readable and faster: ❯ ./python -m timeit -s 'import types; c = dict(zip("abcdefghi", iter(types.CellType, None)))' 'dict(zip(c, map(id, c.values())))' 100000 loops, best of 5: 3.15 usec per loop ❯ ./python -m timeit -s 'import types; c = dict(zip("abcdefghi", iter(types.CellType, None)))' '{name: id(cell) for name, cell in c.items()}' 100000 loops, best of 5: 2.86 usec per loop
JelleZijlstra · Jan 19, 2026 · Jan 14, 2026 · Jan 15, 2026 · Jan 16, 2026 · Jan 16, 2026
commit 416c501a3806154b93c298d080e08e570ac17ba2
@@ -281,8 +281,8 @@ def __eq__(self, other):
             and self.__forward_is_class__ == other.__forward_is_class__
             # Two separate cells are always considered unequal in forward refs.
             and (
-                dict(zip(self.__cell__, map(id, self.__cell__.values())))
-                == dict(zip(other.__cell__, map(id, other.__cell__.values())))
+                {name: id(cell) for name, cell in self.__cell__.items()}
+                == {name: id(cell) for name, cell in other.__cell__.items()}
                 if isinstance(self.__cell__, dict) and isinstance(other.__cell__, dict)
                 else self.__cell__ is other.__cell__
             )