From d053d8ffea0d84dac685cf4c8545e3a8c7546a36 Mon Sep 17 00:00:00 2001
From: Alex Waygood <Alex.Waygood@Gmail.com>
Date: Sat, 22 Jan 2022 09:49:59 +0000
Subject: [PATCH] Make `mapping` attribute read-only on dict views classes
 (#6991)

---
 stdlib/_collections_abc.pyi | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/stdlib/_collections_abc.pyi b/stdlib/_collections_abc.pyi
index 223b5fb8d..bd8d35641 100644
--- a/stdlib/_collections_abc.pyi
+++ b/stdlib/_collections_abc.pyi
@@ -65,14 +65,17 @@ _VT_co = TypeVar("_VT_co", covariant=True)  # Value type covariant containers.
 @final
 class dict_keys(KeysView[_KT_co], Generic[_KT_co, _VT_co]):  # undocumented
     if sys.version_info >= (3, 10):
-        mapping: MappingProxyType[_KT_co, _VT_co]
+        @property
+        def mapping(self) -> MappingProxyType[_KT_co, _VT_co]: ...
 
 @final
 class dict_values(ValuesView[_VT_co], Generic[_KT_co, _VT_co]):  # undocumented
     if sys.version_info >= (3, 10):
-        mapping: MappingProxyType[_KT_co, _VT_co]
+        @property
+        def mapping(self) -> MappingProxyType[_KT_co, _VT_co]: ...
 
 @final
 class dict_items(ItemsView[_KT_co, _VT_co], Generic[_KT_co, _VT_co]):  # undocumented
     if sys.version_info >= (3, 10):
-        mapping: MappingProxyType[_KT_co, _VT_co]
+        @property
+        def mapping(self) -> MappingProxyType[_KT_co, _VT_co]: ...