Added Union operators to WeakKeyDictionary

Added `_ior_`, `__or__`, and `__ror__` methods to WeakKeyDictionary and added corresponding tests to test_weakref.py.

Author: curtisbucher

Lib/test/test_weakref.py

@@ -1624,6 +1624,21 @@ def test_weak_keyed_delitem(self):
         self.assertEqual(len(d), 1)
         self.assertEqual(list(d.keys()), [o2])
 
+    def test_weak_keyed_union_operators(self):
+        class C: pass
+        c1 = C()
+        c2 = C()
+        c3 = C()
+        
+        wvd1 = weakref.WeakKeyDictionary({c1: '1', c2: '2'})
+        wvd2 = weakref.WeakKeyDictionary({c3: '3', c1: '4'})
+
+        wvd3 = wvd1 | wvd2
+        self.assertEqual(dict(wvd3), dict(wvd1) | dict(wvd2))
+
+        wvd1 |= wvd2
+        self.assertEqual(wvd1, wvd3)
+
     def test_weak_valued_delitem(self):
         d = weakref.WeakValueDictionary()
         o1 = Object('1')

Lib/weakref.py

@@ -488,6 +488,20 @@ def update(self, dict=None, /, **kwargs):
         if len(kwargs):
             self.update(kwargs)
 
+    def __ior__(self, other):
+        self.update(other)
+        return self
+
+    def __or__(self, other):
+        c = self.copy()
+        c.update(other)
+        return c
+
+    def __ror__(self, other):
+        c = other.copy()
+        c.update(self)
+        return c
+    
 
 class finalize:
     """Class for finalization of weakrefable objects