gh-136380: Fix import behavior for concurrent.futures.InterpreterPoolExecutor

Lib/concurrent/futures/__init__.py

@@ -17,7 +17,7 @@
                                       wait,
                                       as_completed)
 
-__all__ = (
+__all__ = [
     'FIRST_COMPLETED',
     'FIRST_EXCEPTION',
     'ALL_COMPLETED',
@@ -29,10 +29,21 @@
     'Executor',
     'wait',
     'as_completed',
-    'InterpreterPoolExecutor',
     'ProcessPoolExecutor',
     'ThreadPoolExecutor',
-)
+]
+
+
+_have__interpreters = False
+
+try:
+    import _interpreters
+    _have__interpreters = True
+except ModuleNotFoundError:
+    pass
+
+if _have__interpreters:
+    __all__.append('InterpreterPoolExecutor')
 
 
 def __dir__():
@@ -52,13 +63,9 @@ def __getattr__(name):
         ThreadPoolExecutor = te
         return te
 
-    if name == 'InterpreterPoolExecutor':
-        try:
-            from .interpreter import InterpreterPoolExecutor as ie
-        except ModuleNotFoundError:
-            ie = InterpreterPoolExecutor = None
-        else:
-            InterpreterPoolExecutor = ie
+    if _have__interpreters and name == 'InterpreterPoolExecutor':
+        from .interpreter import InterpreterPoolExecutor as ie
+        InterpreterPoolExecutor = ie
         return ie
 
     raise AttributeError(f"module {__name__!r} has no attribute {name!r}")

Misc/NEWS.d/next/Library/2025-07-07-22-12-32.gh-issue-136380.1b_nXl.rst

@@ -0,0 +1,3 @@
+Raises :exc:`AttributeError` when accessing
+``concurrent.futures.InterpreterPoolExecutor`` and ``_interpreter`` is
+not available.