diff --git a/Lib/test/test_capi/test_function.py b/Lib/test/test_capi/test_function.py
new file mode 100644
index 00000000000..9dca377e28b
--- /dev/null
+++ b/Lib/test/test_capi/test_function.py
@@ -0,0 +1,323 @@
+import unittest
+from test.support import import_helper
+
+
+_testcapi = import_helper.import_module('_testcapi')
+
+
+class FunctionTest(unittest.TestCase):
+    def test_function_get_code(self):
+        # Test PyFunction_GetCode()
+        import types
+
+        def some():
+            pass
+
+        code = _testcapi.function_get_code(some)
+        self.assertIsInstance(code, types.CodeType)
+        self.assertEqual(code, some.__code__)
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_get_code(None)  # not a function
+
+    def test_function_get_globals(self):
+        # Test PyFunction_GetGlobals()
+        def some():
+            pass
+
+        globals_ = _testcapi.function_get_globals(some)
+        self.assertIsInstance(globals_, dict)
+        self.assertEqual(globals_, some.__globals__)
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_get_globals(None)  # not a function
+
+    def test_function_get_module(self):
+        # Test PyFunction_GetModule()
+        def some():
+            pass
+
+        module = _testcapi.function_get_module(some)
+        self.assertIsInstance(module, str)
+        self.assertEqual(module, some.__module__)
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_get_module(None)  # not a function
+
+    def test_function_get_defaults(self):
+        # Test PyFunction_GetDefaults()
+        def some(
+            pos_only1, pos_only2='p',
+            /,
+            zero=0, optional=None,
+            *,
+            kw1,
+            kw2=True,
+        ):
+            pass
+
+        defaults = _testcapi.function_get_defaults(some)
+        self.assertEqual(defaults, ('p', 0, None))
+        self.assertEqual(defaults, some.__defaults__)
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_get_defaults(None)  # not a function
+
+    def test_function_set_defaults(self):
+        # Test PyFunction_SetDefaults()
+        def some(
+            pos_only1, pos_only2='p',
+            /,
+            zero=0, optional=None,
+            *,
+            kw1,
+            kw2=True,
+        ):
+            pass
+
+        old_defaults = ('p', 0, None)
+        self.assertEqual(_testcapi.function_get_defaults(some), old_defaults)
+        self.assertEqual(some.__defaults__, old_defaults)
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_set_defaults(some, 1)  # not tuple or None
+        self.assertEqual(_testcapi.function_get_defaults(some), old_defaults)
+        self.assertEqual(some.__defaults__, old_defaults)
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_set_defaults(1, ())    # not a function
+        self.assertEqual(_testcapi.function_get_defaults(some), old_defaults)
+        self.assertEqual(some.__defaults__, old_defaults)
+
+        new_defaults = ('q', 1, None)
+        _testcapi.function_set_defaults(some, new_defaults)
+        self.assertEqual(_testcapi.function_get_defaults(some), new_defaults)
+        self.assertEqual(some.__defaults__, new_defaults)
+
+        # Empty tuple is fine:
+        new_defaults = ()
+        _testcapi.function_set_defaults(some, new_defaults)
+        self.assertEqual(_testcapi.function_get_defaults(some), new_defaults)
+        self.assertEqual(some.__defaults__, new_defaults)
+
+        class tuplesub(tuple): ...  # tuple subclasses must work
+
+        new_defaults = tuplesub(((1, 2), ['a', 'b'], None))
+        _testcapi.function_set_defaults(some, new_defaults)
+        self.assertEqual(_testcapi.function_get_defaults(some), new_defaults)
+        self.assertEqual(some.__defaults__, new_defaults)
+
+        # `None` is special, it sets `defaults` to `NULL`,
+        # it needs special handling in `_testcapi`:
+        _testcapi.function_set_defaults(some, None)
+        self.assertEqual(_testcapi.function_get_defaults(some), None)
+        self.assertEqual(some.__defaults__, None)
+
+    def test_function_get_kw_defaults(self):
+        # Test PyFunction_GetKwDefaults()
+        def some(
+            pos_only1, pos_only2='p',
+            /,
+            zero=0, optional=None,
+            *,
+            kw1,
+            kw2=True,
+        ):
+            pass
+
+        defaults = _testcapi.function_get_kw_defaults(some)
+        self.assertEqual(defaults, {'kw2': True})
+        self.assertEqual(defaults, some.__kwdefaults__)
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_get_kw_defaults(None)  # not a function
+
+    def test_function_set_kw_defaults(self):
+        # Test PyFunction_SetKwDefaults()
+        def some(
+            pos_only1, pos_only2='p',
+            /,
+            zero=0, optional=None,
+            *,
+            kw1,
+            kw2=True,
+        ):
+            pass
+
+        old_defaults = {'kw2': True}
+        self.assertEqual(_testcapi.function_get_kw_defaults(some), old_defaults)
+        self.assertEqual(some.__kwdefaults__, old_defaults)
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_set_kw_defaults(some, 1)  # not dict or None
+        self.assertEqual(_testcapi.function_get_kw_defaults(some), old_defaults)
+        self.assertEqual(some.__kwdefaults__, old_defaults)
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_set_kw_defaults(1, {})    # not a function
+        self.assertEqual(_testcapi.function_get_kw_defaults(some), old_defaults)
+        self.assertEqual(some.__kwdefaults__, old_defaults)
+
+        new_defaults = {'kw2': (1, 2, 3)}
+        _testcapi.function_set_kw_defaults(some, new_defaults)
+        self.assertEqual(_testcapi.function_get_kw_defaults(some), new_defaults)
+        self.assertEqual(some.__kwdefaults__, new_defaults)
+
+        # Empty dict is fine:
+        new_defaults = {}
+        _testcapi.function_set_kw_defaults(some, new_defaults)
+        self.assertEqual(_testcapi.function_get_kw_defaults(some), new_defaults)
+        self.assertEqual(some.__kwdefaults__, new_defaults)
+
+        class dictsub(dict): ...  # dict subclasses must work
+
+        new_defaults = dictsub({'kw2': None})
+        _testcapi.function_set_kw_defaults(some, new_defaults)
+        self.assertEqual(_testcapi.function_get_kw_defaults(some), new_defaults)
+        self.assertEqual(some.__kwdefaults__, new_defaults)
+
+        # `None` is special, it sets `kwdefaults` to `NULL`,
+        # it needs special handling in `_testcapi`:
+        _testcapi.function_set_kw_defaults(some, None)
+        self.assertEqual(_testcapi.function_get_kw_defaults(some), None)
+        self.assertEqual(some.__kwdefaults__, None)
+
+    def test_function_get_closure(self):
+        # Test PyFunction_GetClosure()
+        from types import CellType
+
+        def regular_function(): ...
+        def unused_one_level(arg1):
+            def inner(arg2, arg3): ...
+            return inner
+        def unused_two_levels(arg1, arg2):
+            def decorator(arg3, arg4):
+                def inner(arg5, arg6): ...
+                return inner
+            return decorator
+        def with_one_level(arg1):
+            def inner(arg2, arg3):
+                return arg1 + arg2 + arg3
+            return inner
+        def with_two_levels(arg1, arg2):
+            def decorator(arg3, arg4):
+                def inner(arg5, arg6):
+                    return arg1 + arg2 + arg3 + arg4 + arg5 + arg6
+                return inner
+            return decorator
+
+        # Functions without closures:
+        self.assertIsNone(_testcapi.function_get_closure(regular_function))
+        self.assertIsNone(regular_function.__closure__)
+
+        func = unused_one_level(1)
+        closure = _testcapi.function_get_closure(func)
+        self.assertIsNone(closure)
+        self.assertIsNone(func.__closure__)
+
+        func = unused_two_levels(1, 2)(3, 4)
+        closure = _testcapi.function_get_closure(func)
+        self.assertIsNone(closure)
+        self.assertIsNone(func.__closure__)
+
+        # Functions with closures:
+        func = with_one_level(5)
+        closure = _testcapi.function_get_closure(func)
+        self.assertEqual(closure, func.__closure__)
+        self.assertIsInstance(closure, tuple)
+        self.assertEqual(len(closure), 1)
+        self.assertEqual(len(closure), len(func.__code__.co_freevars))
+        for cell in closure:
+            self.assertIsInstance(cell, CellType)
+        self.assertTrue(closure[0].cell_contents, 5)
+
+        func = with_two_levels(1, 2)(3, 4)
+        closure = _testcapi.function_get_closure(func)
+        self.assertEqual(closure, func.__closure__)
+        self.assertIsInstance(closure, tuple)
+        self.assertEqual(len(closure), 4)
+        self.assertEqual(len(closure), len(func.__code__.co_freevars))
+        for cell in closure:
+            self.assertIsInstance(cell, CellType)
+        self.assertEqual([cell.cell_contents for cell in closure],
+                         [1, 2, 3, 4])
+
+    def test_function_get_closure_error(self):
+        # Test PyFunction_GetClosure()
+        with self.assertRaises(SystemError):
+            _testcapi.function_get_closure(1)
+        with self.assertRaises(SystemError):
+            _testcapi.function_get_closure(None)
+
+    def test_function_set_closure(self):
+        # Test PyFunction_SetClosure()
+        from types import CellType
+
+        def function_without_closure(): ...
+        def function_with_closure(arg):
+            def inner():
+                return arg
+            return inner
+
+        func = function_without_closure
+        _testcapi.function_set_closure(func, (CellType(1), CellType(1)))
+        closure = _testcapi.function_get_closure(func)
+        self.assertEqual([c.cell_contents for c in closure], [1, 1])
+        self.assertEqual([c.cell_contents for c in func.__closure__], [1, 1])
+
+        func = function_with_closure(1)
+        _testcapi.function_set_closure(func,
+                                       (CellType(1), CellType(2), CellType(3)))
+        closure = _testcapi.function_get_closure(func)
+        self.assertEqual([c.cell_contents for c in closure], [1, 2, 3])
+        self.assertEqual([c.cell_contents for c in func.__closure__], [1, 2, 3])
+
+    def test_function_set_closure_none(self):
+        # Test PyFunction_SetClosure()
+        def function_without_closure(): ...
+        def function_with_closure(arg):
+            def inner():
+                return arg
+            return inner
+
+        _testcapi.function_set_closure(function_without_closure, None)
+        self.assertIsNone(
+            _testcapi.function_get_closure(function_without_closure))
+        self.assertIsNone(function_without_closure.__closure__)
+
+        _testcapi.function_set_closure(function_with_closure, None)
+        self.assertIsNone(
+            _testcapi.function_get_closure(function_with_closure))
+        self.assertIsNone(function_with_closure.__closure__)
+
+    def test_function_set_closure_errors(self):
+        # Test PyFunction_SetClosure()
+        def function_without_closure(): ...
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_set_closure(None, ())  # not a function
+
+        with self.assertRaises(SystemError):
+            _testcapi.function_set_closure(function_without_closure, 1)
+        self.assertIsNone(function_without_closure.__closure__)  # no change
+
+        # NOTE: this works, but goes against the docs:
+        _testcapi.function_set_closure(function_without_closure, (1, 2))
+        self.assertEqual(
+            _testcapi.function_get_closure(function_without_closure), (1, 2))
+        self.assertEqual(function_without_closure.__closure__, (1, 2))
+
+    # TODO: test PyFunction_New()
+    # TODO: test PyFunction_NewWithQualName()
+    # TODO: test PyFunction_SetVectorcall()
+    # TODO: test PyFunction_GetAnnotations()
+    # TODO: test PyFunction_SetAnnotations()
+    # TODO: test PyClassMethod_New()
+    # TODO: test PyStaticMethod_New()
+    #
+    # PyFunction_AddWatcher() and PyFunction_ClearWatcher() are tested by
+    # test_capi.test_watchers.
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/Lib/test/test_capi/test_misc.py b/Lib/test/test_capi/test_misc.py
index efa01a84167..acc4803d785 100644
--- a/Lib/test/test_capi/test_misc.py
+++ b/Lib/test/test_capi/test_misc.py
@@ -928,175 +928,6 @@ def __init__(self):
         _testcapi.clear_managed_dict(c)
         self.assertEqual(c.__dict__, {})
 
-    def test_function_get_code(self):
-        import types
-
-        def some():
-            pass
-
-        code = _testcapi.function_get_code(some)
-        self.assertIsInstance(code, types.CodeType)
-        self.assertEqual(code, some.__code__)
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_get_code(None)  # not a function
-
-    def test_function_get_globals(self):
-        def some():
-            pass
-
-        globals_ = _testcapi.function_get_globals(some)
-        self.assertIsInstance(globals_, dict)
-        self.assertEqual(globals_, some.__globals__)
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_get_globals(None)  # not a function
-
-    def test_function_get_module(self):
-        def some():
-            pass
-
-        module = _testcapi.function_get_module(some)
-        self.assertIsInstance(module, str)
-        self.assertEqual(module, some.__module__)
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_get_module(None)  # not a function
-
-    def test_function_get_defaults(self):
-        def some(
-            pos_only1, pos_only2='p',
-            /,
-            zero=0, optional=None,
-            *,
-            kw1,
-            kw2=True,
-        ):
-            pass
-
-        defaults = _testcapi.function_get_defaults(some)
-        self.assertEqual(defaults, ('p', 0, None))
-        self.assertEqual(defaults, some.__defaults__)
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_get_defaults(None)  # not a function
-
-    def test_function_set_defaults(self):
-        def some(
-            pos_only1, pos_only2='p',
-            /,
-            zero=0, optional=None,
-            *,
-            kw1,
-            kw2=True,
-        ):
-            pass
-
-        old_defaults = ('p', 0, None)
-        self.assertEqual(_testcapi.function_get_defaults(some), old_defaults)
-        self.assertEqual(some.__defaults__, old_defaults)
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_set_defaults(some, 1)  # not tuple or None
-        self.assertEqual(_testcapi.function_get_defaults(some), old_defaults)
-        self.assertEqual(some.__defaults__, old_defaults)
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_set_defaults(1, ())    # not a function
-        self.assertEqual(_testcapi.function_get_defaults(some), old_defaults)
-        self.assertEqual(some.__defaults__, old_defaults)
-
-        new_defaults = ('q', 1, None)
-        _testcapi.function_set_defaults(some, new_defaults)
-        self.assertEqual(_testcapi.function_get_defaults(some), new_defaults)
-        self.assertEqual(some.__defaults__, new_defaults)
-
-        # Empty tuple is fine:
-        new_defaults = ()
-        _testcapi.function_set_defaults(some, new_defaults)
-        self.assertEqual(_testcapi.function_get_defaults(some), new_defaults)
-        self.assertEqual(some.__defaults__, new_defaults)
-
-        class tuplesub(tuple): ...  # tuple subclasses must work
-
-        new_defaults = tuplesub(((1, 2), ['a', 'b'], None))
-        _testcapi.function_set_defaults(some, new_defaults)
-        self.assertEqual(_testcapi.function_get_defaults(some), new_defaults)
-        self.assertEqual(some.__defaults__, new_defaults)
-
-        # `None` is special, it sets `defaults` to `NULL`,
-        # it needs special handling in `_testcapi`:
-        _testcapi.function_set_defaults(some, None)
-        self.assertEqual(_testcapi.function_get_defaults(some), None)
-        self.assertEqual(some.__defaults__, None)
-
-    def test_function_get_kw_defaults(self):
-        def some(
-            pos_only1, pos_only2='p',
-            /,
-            zero=0, optional=None,
-            *,
-            kw1,
-            kw2=True,
-        ):
-            pass
-
-        defaults = _testcapi.function_get_kw_defaults(some)
-        self.assertEqual(defaults, {'kw2': True})
-        self.assertEqual(defaults, some.__kwdefaults__)
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_get_kw_defaults(None)  # not a function
-
-    def test_function_set_kw_defaults(self):
-        def some(
-            pos_only1, pos_only2='p',
-            /,
-            zero=0, optional=None,
-            *,
-            kw1,
-            kw2=True,
-        ):
-            pass
-
-        old_defaults = {'kw2': True}
-        self.assertEqual(_testcapi.function_get_kw_defaults(some), old_defaults)
-        self.assertEqual(some.__kwdefaults__, old_defaults)
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_set_kw_defaults(some, 1)  # not dict or None
-        self.assertEqual(_testcapi.function_get_kw_defaults(some), old_defaults)
-        self.assertEqual(some.__kwdefaults__, old_defaults)
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_set_kw_defaults(1, {})    # not a function
-        self.assertEqual(_testcapi.function_get_kw_defaults(some), old_defaults)
-        self.assertEqual(some.__kwdefaults__, old_defaults)
-
-        new_defaults = {'kw2': (1, 2, 3)}
-        _testcapi.function_set_kw_defaults(some, new_defaults)
-        self.assertEqual(_testcapi.function_get_kw_defaults(some), new_defaults)
-        self.assertEqual(some.__kwdefaults__, new_defaults)
-
-        # Empty dict is fine:
-        new_defaults = {}
-        _testcapi.function_set_kw_defaults(some, new_defaults)
-        self.assertEqual(_testcapi.function_get_kw_defaults(some), new_defaults)
-        self.assertEqual(some.__kwdefaults__, new_defaults)
-
-        class dictsub(dict): ...  # dict subclasses must work
-
-        new_defaults = dictsub({'kw2': None})
-        _testcapi.function_set_kw_defaults(some, new_defaults)
-        self.assertEqual(_testcapi.function_get_kw_defaults(some), new_defaults)
-        self.assertEqual(some.__kwdefaults__, new_defaults)
-
-        # `None` is special, it sets `kwdefaults` to `NULL`,
-        # it needs special handling in `_testcapi`:
-        _testcapi.function_set_kw_defaults(some, None)
-        self.assertEqual(_testcapi.function_get_kw_defaults(some), None)
-        self.assertEqual(some.__kwdefaults__, None)
-
     def test_unstable_gc_new_with_extra_data(self):
         class Data(_testcapi.ObjExtraData):
             __slots__ = ('x', 'y')
@@ -1319,127 +1150,6 @@ def test_pyobject_getitemdata_error(self):
             _testcapi.pyobject_getitemdata(0)
 
 
-    def test_function_get_closure(self):
-        from types import CellType
-
-        def regular_function(): ...
-        def unused_one_level(arg1):
-            def inner(arg2, arg3): ...
-            return inner
-        def unused_two_levels(arg1, arg2):
-            def decorator(arg3, arg4):
-                def inner(arg5, arg6): ...
-                return inner
-            return decorator
-        def with_one_level(arg1):
-            def inner(arg2, arg3):
-                return arg1 + arg2 + arg3
-            return inner
-        def with_two_levels(arg1, arg2):
-            def decorator(arg3, arg4):
-                def inner(arg5, arg6):
-                    return arg1 + arg2 + arg3 + arg4 + arg5 + arg6
-                return inner
-            return decorator
-
-        # Functions without closures:
-        self.assertIsNone(_testcapi.function_get_closure(regular_function))
-        self.assertIsNone(regular_function.__closure__)
-
-        func = unused_one_level(1)
-        closure = _testcapi.function_get_closure(func)
-        self.assertIsNone(closure)
-        self.assertIsNone(func.__closure__)
-
-        func = unused_two_levels(1, 2)(3, 4)
-        closure = _testcapi.function_get_closure(func)
-        self.assertIsNone(closure)
-        self.assertIsNone(func.__closure__)
-
-        # Functions with closures:
-        func = with_one_level(5)
-        closure = _testcapi.function_get_closure(func)
-        self.assertEqual(closure, func.__closure__)
-        self.assertIsInstance(closure, tuple)
-        self.assertEqual(len(closure), 1)
-        self.assertEqual(len(closure), len(func.__code__.co_freevars))
-        for cell in closure:
-            self.assertIsInstance(cell, CellType)
-        self.assertTrue(closure[0].cell_contents, 5)
-
-        func = with_two_levels(1, 2)(3, 4)
-        closure = _testcapi.function_get_closure(func)
-        self.assertEqual(closure, func.__closure__)
-        self.assertIsInstance(closure, tuple)
-        self.assertEqual(len(closure), 4)
-        self.assertEqual(len(closure), len(func.__code__.co_freevars))
-        for cell in closure:
-            self.assertIsInstance(cell, CellType)
-        self.assertEqual([cell.cell_contents for cell in closure],
-                         [1, 2, 3, 4])
-
-    def test_function_get_closure_error(self):
-        with self.assertRaises(SystemError):
-            _testcapi.function_get_closure(1)
-        with self.assertRaises(SystemError):
-            _testcapi.function_get_closure(None)
-
-    def test_function_set_closure(self):
-        from types import CellType
-
-        def function_without_closure(): ...
-        def function_with_closure(arg):
-            def inner():
-                return arg
-            return inner
-
-        func = function_without_closure
-        _testcapi.function_set_closure(func, (CellType(1), CellType(1)))
-        closure = _testcapi.function_get_closure(func)
-        self.assertEqual([c.cell_contents for c in closure], [1, 1])
-        self.assertEqual([c.cell_contents for c in func.__closure__], [1, 1])
-
-        func = function_with_closure(1)
-        _testcapi.function_set_closure(func,
-                                       (CellType(1), CellType(2), CellType(3)))
-        closure = _testcapi.function_get_closure(func)
-        self.assertEqual([c.cell_contents for c in closure], [1, 2, 3])
-        self.assertEqual([c.cell_contents for c in func.__closure__], [1, 2, 3])
-
-    def test_function_set_closure_none(self):
-        def function_without_closure(): ...
-        def function_with_closure(arg):
-            def inner():
-                return arg
-            return inner
-
-        _testcapi.function_set_closure(function_without_closure, None)
-        self.assertIsNone(
-            _testcapi.function_get_closure(function_without_closure))
-        self.assertIsNone(function_without_closure.__closure__)
-
-        _testcapi.function_set_closure(function_with_closure, None)
-        self.assertIsNone(
-            _testcapi.function_get_closure(function_with_closure))
-        self.assertIsNone(function_with_closure.__closure__)
-
-    def test_function_set_closure_errors(self):
-        def function_without_closure(): ...
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_set_closure(None, ())  # not a function
-
-        with self.assertRaises(SystemError):
-            _testcapi.function_set_closure(function_without_closure, 1)
-        self.assertIsNone(function_without_closure.__closure__)  # no change
-
-        # NOTE: this works, but goes against the docs:
-        _testcapi.function_set_closure(function_without_closure, (1, 2))
-        self.assertEqual(
-            _testcapi.function_get_closure(function_without_closure), (1, 2))
-        self.assertEqual(function_without_closure.__closure__, (1, 2))
-
-
 class TestPendingCalls(unittest.TestCase):
 
     # See the comment in ceval.c (at the "handle_eval_breaker" label)
@@ -3209,5 +2919,6 @@ def test_pack_version_ctypes(self):
                 result = ctypes_func(*args)
                 self.assertEqual(result, expected)
 
+
 if __name__ == "__main__":
     unittest.main()
diff --git a/Modules/Setup.stdlib.in b/Modules/Setup.stdlib.in
index a276fa642de..6bb05a06a34 100644
--- a/Modules/Setup.stdlib.in
+++ b/Modules/Setup.stdlib.in
@@ -162,7 +162,7 @@
 @MODULE__XXTESTFUZZ_TRUE@_xxtestfuzz _xxtestfuzz/_xxtestfuzz.c _xxtestfuzz/fuzzer.c
 @MODULE__TESTBUFFER_TRUE@_testbuffer _testbuffer.c
 @MODULE__TESTINTERNALCAPI_TRUE@_testinternalcapi _testinternalcapi.c _testinternalcapi/test_lock.c _testinternalcapi/pytime.c _testinternalcapi/set.c _testinternalcapi/test_critical_sections.c
-@MODULE__TESTCAPI_TRUE@_testcapi _testcapimodule.c _testcapi/vectorcall.c _testcapi/heaptype.c _testcapi/abstract.c _testcapi/unicode.c _testcapi/dict.c _testcapi/set.c _testcapi/list.c _testcapi/tuple.c _testcapi/getargs.c _testcapi/datetime.c _testcapi/docstring.c _testcapi/mem.c _testcapi/watchers.c _testcapi/long.c _testcapi/float.c _testcapi/complex.c _testcapi/numbers.c _testcapi/structmember.c _testcapi/exceptions.c _testcapi/code.c _testcapi/buffer.c _testcapi/pyatomic.c _testcapi/run.c _testcapi/file.c _testcapi/codec.c _testcapi/immortal.c _testcapi/gc.c _testcapi/hash.c _testcapi/time.c _testcapi/bytes.c _testcapi/object.c _testcapi/monitoring.c _testcapi/config.c _testcapi/import.c _testcapi/frame.c _testcapi/type.c
+@MODULE__TESTCAPI_TRUE@_testcapi _testcapimodule.c _testcapi/vectorcall.c _testcapi/heaptype.c _testcapi/abstract.c _testcapi/unicode.c _testcapi/dict.c _testcapi/set.c _testcapi/list.c _testcapi/tuple.c _testcapi/getargs.c _testcapi/datetime.c _testcapi/docstring.c _testcapi/mem.c _testcapi/watchers.c _testcapi/long.c _testcapi/float.c _testcapi/complex.c _testcapi/numbers.c _testcapi/structmember.c _testcapi/exceptions.c _testcapi/code.c _testcapi/buffer.c _testcapi/pyatomic.c _testcapi/run.c _testcapi/file.c _testcapi/codec.c _testcapi/immortal.c _testcapi/gc.c _testcapi/hash.c _testcapi/time.c _testcapi/bytes.c _testcapi/object.c _testcapi/monitoring.c _testcapi/config.c _testcapi/import.c _testcapi/frame.c _testcapi/type.c _testcapi/function.c
 @MODULE__TESTLIMITEDCAPI_TRUE@_testlimitedcapi _testlimitedcapi.c _testlimitedcapi/abstract.c _testlimitedcapi/bytearray.c _testlimitedcapi/bytes.c _testlimitedcapi/codec.c _testlimitedcapi/complex.c _testlimitedcapi/dict.c _testlimitedcapi/eval.c _testlimitedcapi/float.c _testlimitedcapi/heaptype_relative.c _testlimitedcapi/import.c _testlimitedcapi/list.c _testlimitedcapi/long.c _testlimitedcapi/object.c _testlimitedcapi/pyos.c _testlimitedcapi/set.c _testlimitedcapi/sys.c _testlimitedcapi/tuple.c _testlimitedcapi/unicode.c _testlimitedcapi/vectorcall_limited.c _testlimitedcapi/version.c _testlimitedcapi/file.c
 @MODULE__TESTCLINIC_TRUE@_testclinic _testclinic.c
 @MODULE__TESTCLINIC_LIMITED_TRUE@_testclinic_limited _testclinic_limited.c
diff --git a/Modules/_testcapi/function.c b/Modules/_testcapi/function.c
new file mode 100644
index 00000000000..ec1ba508df2
--- /dev/null
+++ b/Modules/_testcapi/function.c
@@ -0,0 +1,143 @@
+#include "parts.h"
+#include "util.h"
+
+
+static PyObject *
+function_get_code(PyObject *self, PyObject *func)
+{
+    PyObject *code = PyFunction_GetCode(func);
+    if (code != NULL) {
+        return Py_NewRef(code);
+    } else {
+        return NULL;
+    }
+}
+
+
+static PyObject *
+function_get_globals(PyObject *self, PyObject *func)
+{
+    PyObject *globals = PyFunction_GetGlobals(func);
+    if (globals != NULL) {
+        return Py_NewRef(globals);
+    } else {
+        return NULL;
+    }
+}
+
+
+static PyObject *
+function_get_module(PyObject *self, PyObject *func)
+{
+    PyObject *module = PyFunction_GetModule(func);
+    if (module != NULL) {
+        return Py_NewRef(module);
+    } else {
+        return NULL;
+    }
+}
+
+
+static PyObject *
+function_get_defaults(PyObject *self, PyObject *func)
+{
+    PyObject *defaults = PyFunction_GetDefaults(func);
+    if (defaults != NULL) {
+        return Py_NewRef(defaults);
+    } else if (PyErr_Occurred()) {
+        return NULL;
+    } else {
+        Py_RETURN_NONE;  // This can happen when `defaults` are set to `None`
+    }
+}
+
+
+static PyObject *
+function_set_defaults(PyObject *self, PyObject *args)
+{
+    PyObject *func = NULL, *defaults = NULL;
+    if (!PyArg_ParseTuple(args, "OO", &func, &defaults)) {
+        return NULL;
+    }
+    int result = PyFunction_SetDefaults(func, defaults);
+    if (result == -1)
+        return NULL;
+    Py_RETURN_NONE;
+}
+
+
+static PyObject *
+function_get_kw_defaults(PyObject *self, PyObject *func)
+{
+    PyObject *defaults = PyFunction_GetKwDefaults(func);
+    if (defaults != NULL) {
+        return Py_NewRef(defaults);
+    } else if (PyErr_Occurred()) {
+        return NULL;
+    } else {
+        Py_RETURN_NONE;  // This can happen when `kwdefaults` are set to `None`
+    }
+}
+
+
+static PyObject *
+function_set_kw_defaults(PyObject *self, PyObject *args)
+{
+    PyObject *func = NULL, *defaults = NULL;
+    if (!PyArg_ParseTuple(args, "OO", &func, &defaults)) {
+        return NULL;
+    }
+    int result = PyFunction_SetKwDefaults(func, defaults);
+    if (result == -1)
+        return NULL;
+    Py_RETURN_NONE;
+}
+
+
+static PyObject *
+function_get_closure(PyObject *self, PyObject *func)
+{
+    PyObject *closure = PyFunction_GetClosure(func);
+    if (closure != NULL) {
+        return Py_NewRef(closure);
+    } else if (PyErr_Occurred()) {
+        return NULL;
+    } else {
+        Py_RETURN_NONE;  // This can happen when `closure` is set to `None`
+    }
+}
+
+
+static PyObject *
+function_set_closure(PyObject *self, PyObject *args)
+{
+    PyObject *func = NULL, *closure = NULL;
+    if (!PyArg_ParseTuple(args, "OO", &func, &closure)) {
+        return NULL;
+    }
+    int result = PyFunction_SetClosure(func, closure);
+    if (result == -1) {
+        return NULL;
+    }
+    Py_RETURN_NONE;
+}
+
+
+static PyMethodDef test_methods[] = {
+    {"function_get_code", function_get_code, METH_O, NULL},
+    {"function_get_globals", function_get_globals, METH_O, NULL},
+    {"function_get_module", function_get_module, METH_O, NULL},
+    {"function_get_defaults", function_get_defaults, METH_O, NULL},
+    {"function_set_defaults", function_set_defaults, METH_VARARGS, NULL},
+    {"function_get_kw_defaults", function_get_kw_defaults, METH_O, NULL},
+    {"function_set_kw_defaults", function_set_kw_defaults, METH_VARARGS, NULL},
+    {"function_get_closure", function_get_closure, METH_O, NULL},
+    {"function_set_closure", function_set_closure, METH_VARARGS, NULL},
+    {NULL},
+};
+
+int
+_PyTestCapi_Init_Function(PyObject *m)
+{
+    return PyModule_AddFunctions(m, test_methods);
+}
diff --git a/Modules/_testcapi/parts.h b/Modules/_testcapi/parts.h
index c4b73459b37..af6400162da 100644
--- a/Modules/_testcapi/parts.h
+++ b/Modules/_testcapi/parts.h
@@ -64,5 +64,6 @@ int _PyTestCapi_Init_Config(PyObject *mod);
 int _PyTestCapi_Init_Import(PyObject *mod);
 int _PyTestCapi_Init_Frame(PyObject *mod);
 int _PyTestCapi_Init_Type(PyObject *mod);
+int _PyTestCapi_Init_Function(PyObject *mod);
 
 #endif // Py_TESTCAPI_PARTS_H
diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c
index ad9d836120b..5b5b630e7e7 100644
--- a/Modules/_testcapimodule.c
+++ b/Modules/_testcapimodule.c
@@ -2652,119 +2652,6 @@ test_macros(PyObject *self, PyObject *Py_UNUSED(args))
     Py_RETURN_NONE;
 }
 
-static PyObject *
-function_get_code(PyObject *self, PyObject *func)
-{
-    PyObject *code = PyFunction_GetCode(func);
-    if (code != NULL) {
-        return Py_NewRef(code);
-    } else {
-        return NULL;
-    }
-}
-
-static PyObject *
-function_get_globals(PyObject *self, PyObject *func)
-{
-    PyObject *globals = PyFunction_GetGlobals(func);
-    if (globals != NULL) {
-        return Py_NewRef(globals);
-    } else {
-        return NULL;
-    }
-}
-
-static PyObject *
-function_get_module(PyObject *self, PyObject *func)
-{
-    PyObject *module = PyFunction_GetModule(func);
-    if (module != NULL) {
-        return Py_NewRef(module);
-    } else {
-        return NULL;
-    }
-}
-
-static PyObject *
-function_get_defaults(PyObject *self, PyObject *func)
-{
-    PyObject *defaults = PyFunction_GetDefaults(func);
-    if (defaults != NULL) {
-        return Py_NewRef(defaults);
-    } else if (PyErr_Occurred()) {
-        return NULL;
-    } else {
-        Py_RETURN_NONE;  // This can happen when `defaults` are set to `None`
-    }
-}
-
-static PyObject *
-function_set_defaults(PyObject *self, PyObject *args)
-{
-    PyObject *func = NULL, *defaults = NULL;
-    if (!PyArg_ParseTuple(args, "OO", &func, &defaults)) {
-        return NULL;
-    }
-    int result = PyFunction_SetDefaults(func, defaults);
-    if (result == -1)
-        return NULL;
-    Py_RETURN_NONE;
-}
-
-static PyObject *
-function_get_kw_defaults(PyObject *self, PyObject *func)
-{
-    PyObject *defaults = PyFunction_GetKwDefaults(func);
-    if (defaults != NULL) {
-        return Py_NewRef(defaults);
-    } else if (PyErr_Occurred()) {
-        return NULL;
-    } else {
-        Py_RETURN_NONE;  // This can happen when `kwdefaults` are set to `None`
-    }
-}
-
-static PyObject *
-function_set_kw_defaults(PyObject *self, PyObject *args)
-{
-    PyObject *func = NULL, *defaults = NULL;
-    if (!PyArg_ParseTuple(args, "OO", &func, &defaults)) {
-        return NULL;
-    }
-    int result = PyFunction_SetKwDefaults(func, defaults);
-    if (result == -1)
-        return NULL;
-    Py_RETURN_NONE;
-}
-
-static PyObject *
-function_get_closure(PyObject *self, PyObject *func)
-{
-    PyObject *closure = PyFunction_GetClosure(func);
-    if (closure != NULL) {
-        return Py_NewRef(closure);
-    } else if (PyErr_Occurred()) {
-        return NULL;
-    } else {
-        Py_RETURN_NONE;  // This can happen when `closure` is set to `None`
-    }
-}
-
-static PyObject *
-function_set_closure(PyObject *self, PyObject *args)
-{
-    PyObject *func = NULL, *closure = NULL;
-    if (!PyArg_ParseTuple(args, "OO", &func, &closure)) {
-        return NULL;
-    }
-    int result = PyFunction_SetClosure(func, closure);
-    if (result == -1) {
-        return NULL;
-    }
-    Py_RETURN_NONE;
-}
-
-
 static PyObject *
 test_weakref_capi(PyObject *Py_UNUSED(module), PyObject *Py_UNUSED(args))
 {
@@ -3286,15 +3173,6 @@ static PyMethodDef TestMethods[] = {
     {"settrace_to_record", settrace_to_record, METH_O, NULL},
     {"test_macros", test_macros, METH_NOARGS, NULL},
     {"clear_managed_dict", clear_managed_dict, METH_O, NULL},
-    {"function_get_code", function_get_code, METH_O, NULL},
-    {"function_get_globals", function_get_globals, METH_O, NULL},
-    {"function_get_module", function_get_module, METH_O, NULL},
-    {"function_get_defaults", function_get_defaults, METH_O, NULL},
-    {"function_set_defaults", function_set_defaults, METH_VARARGS, NULL},
-    {"function_get_kw_defaults", function_get_kw_defaults, METH_O, NULL},
-    {"function_set_kw_defaults", function_set_kw_defaults, METH_VARARGS, NULL},
-    {"function_get_closure", function_get_closure, METH_O, NULL},
-    {"function_set_closure", function_set_closure, METH_VARARGS, NULL},
     {"test_weakref_capi", test_weakref_capi, METH_NOARGS},
     {"function_set_warning", function_set_warning, METH_NOARGS},
     {"test_critical_sections", test_critical_sections, METH_NOARGS},
@@ -4081,6 +3959,9 @@ PyInit__testcapi(void)
     if (_PyTestCapi_Init_Type(m) < 0) {
         return NULL;
     }
+    if (_PyTestCapi_Init_Function(m) < 0) {
+        return NULL;
+    }
 
     PyState_AddModule(m, &_testcapimodule);
     return m;
diff --git a/PCbuild/_testcapi.vcxproj b/PCbuild/_testcapi.vcxproj
index 09969331c6e..a68f15d25aa 100644
--- a/PCbuild/_testcapi.vcxproj
+++ b/PCbuild/_testcapi.vcxproj
@@ -130,6 +130,7 @@
     <ClCompile Include="..\Modules\_testcapi\import.c" />
     <ClCompile Include="..\Modules\_testcapi\frame.c" />
     <ClCompile Include="..\Modules\_testcapi\type.c" />
+    <ClCompile Include="..\Modules\_testcapi\function.c" />
   </ItemGroup>
   <ItemGroup>
     <ResourceCompile Include="..\PC\python_nt.rc" />
diff --git a/PCbuild/_testcapi.vcxproj.filters b/PCbuild/_testcapi.vcxproj.filters
index 52491643ad8..21091e9dc1a 100644
--- a/PCbuild/_testcapi.vcxproj.filters
+++ b/PCbuild/_testcapi.vcxproj.filters
@@ -123,6 +123,9 @@
     <ClCompile Include="..\Modules\_testcapi\type.c">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="..\Modules\_testcapi\function.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ResourceCompile Include="..\PC\python_nt.rc">