Fix profiler on cpython-3.13 (pytorch#154037)

Fix profiler on cpython-3.13 (pytorch#153848)

Per [PEP 667](https://peps.python.org/pep-0667/) `PyFrame_GetLocals` no longer returns dict, but rather instance of `PyFrameLocalsProxy_Type`, so calling `PyDict_GetItemString` is no longer valid(it will always return None) and must be replaced with `PyMapping_GetItemString`

Tested by partially reverting pytorch#141674 full revert will be done in the followup PR

Fixes pytorch#148273
Pull Request resolved: pytorch#153848
Approved by: https://github.com/Skylion007

(cherry picked from commit c0343b1)

Co-authored-by: Nikita Shulga <[email protected]>

Author: pytorchbot

test/profiler/test_profiler.py

@@ -226,7 +226,6 @@ def custom_layer(input_ten):
             q.backward()
 
 
-@unittest.skipIf(sys.version_info >= (3, 13), "segfaults")
 @instantiate_parametrized_tests
 class TestProfiler(TestCase):
     @unittest.skipIf(
@@ -2308,7 +2307,6 @@ def __init__(self, name, children) -> None:
         self.children = [MockNode(name, i) for name, i in children.items()]
 
 
-@unittest.skipIf(sys.version_info >= (3, 13), "segfaults")
 class TestExperimentalUtils(TestCase):
     def make_tree(self) -> list[MockNode]:
         tree = {

torch/csrc/autograd/profiler_python.cpp

@@ -862,15 +862,26 @@ void PythonTracer::recordPyCall(
       // `PyFrame_FastToLocals` which forces the interpreter to materialize
       // the full dict of locals.
       auto locals = THPObjectPtr(PyFrame_GetLocals(frame));
+
+#if PY_MAJOR_VERSION < 3 || (PY_MAJOR_VERSION == 3 && PY_MINOR_VERSION < 13)
       auto self = THPObjectPtr(PyDict_GetItemString(locals, "self"));
+#else
+      // In Python-3.13+ `PyFrame_GetLocals()` returns instance of
+      // PyFrameLocalsProxy_Type See PEP 667 for more info
+      auto self = THPObjectPtr(PyMapping_GetItemString(locals, "self"));
+#endif
       Py_INCREF(self.get());
       auto back = THPFrameObjectPtr(PyFrame_GetBack(frame));
       TORCH_INTERNAL_ASSERT(back != nullptr);
       return tls.intern<CallType::PyModuleCall, E>(
           frame, self.get(), back.get());
     } else if (code.get() == optimizer_hook_) {
       auto locals = THPObjectPtr(PyFrame_GetLocals(frame));
+#if PY_MAJOR_VERSION < 3 || (PY_MAJOR_VERSION == 3 && PY_MINOR_VERSION < 13)
       auto self = THPObjectPtr(PyDict_GetItemString(locals, "self"));
+#else
+      auto self = THPObjectPtr(PyMapping_GetItemString(locals, "self"));
+#endif
       Py_INCREF(self.get());
       auto back = THPFrameObjectPtr(PyFrame_GetBack(frame));
       TORCH_INTERNAL_ASSERT(back != nullptr);