bpo-44019: Implement operator.call(). (GH-27888)

Having `operator.call(obj, arg)` mean `type(obj).__call__(obj, arg)` is
consistent with the other dunder operators.  The semantics with `*args,
**kwargs` then follow naturally from the single-arg semantics.

2 files changed, 19 insertions, 0 deletions

diff --git a/Lib/operator.py b/Lib/operator.py
index 241fdbb..72105be 100644
--- a/Lib/operator.py
+++ b/Lib/operator.py
@@ -221,6 +221,12 @@ def length_hint(obj, default=0):
         raise ValueError(msg)
     return val
 
+# Other Operations ************************************************************#
+
+def call(obj, /, *args, **kwargs):
+    """Same as obj(*args, **kwargs)."""
+    return obj(*args, **kwargs)
+
 # Generalized Lookup Objects **************************************************#
 
 class attrgetter:
@@ -423,6 +429,7 @@ __not__ = not_
 __abs__ = abs
 __add__ = add
 __and__ = and_
+__call__ = call
 __floordiv__ = floordiv
 __index__ = index
 __inv__ = inv
diff --git a/Lib/test/test_operator.py b/Lib/test/test_operator.py
index b9b8f15..cf3439f 100644
--- a/Lib/test/test_operator.py
+++ b/Lib/test/test_operator.py
@@ -518,6 +518,18 @@ class OperatorTestCase:
         with self.assertRaises(LookupError):
             operator.length_hint(X(LookupError))
 
+    def test_call(self):
+        operator = self.module
+
+        def func(*args, **kwargs): return args, kwargs
+
+        self.assertEqual(operator.call(func), ((), {}))
+        self.assertEqual(operator.call(func, 0, 1), ((0, 1), {}))
+        self.assertEqual(operator.call(func, a=2, obj=3),
+                         ((), {"a": 2, "obj": 3}))
+        self.assertEqual(operator.call(func, 0, 1, a=2, obj=3),
+                         ((0, 1), {"a": 2, "obj": 3}))
+
     def test_dunder_is_original(self):
         operator = self.module