GeezerVison

$ python3
Python 3.9.12 (main, Mar 26 2022, 15:52:10) 
[Clang 13.0.0 (clang-1300.0.29.30)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> class A: pass
... 
>>> A.x
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: type object 'A' has no attribute 'x'
>>> del A.x
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: x
>>> A().x
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'A' object has no attribute 'x'
>>> del A().x
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: x

$ pypy3
Python 3.7.13 (7e0ae751533460d5f89f3ac48ce366d8642d1db5, Apr 26 2022, 09:31:20)
[PyPy 7.3.9 with GCC Apple LLVM 13.0.0 (clang-1300.0.29.30)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>> class A: pass
>>>> 
>>>> A.x
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: type object 'A' has no attribute 'x'
>>>> del A.x
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'type' object has no attribute 'x'
>>>> A().x
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'A' object has no attribute 'x'
>>>> del A().x
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'A' object has no attribute 'x'

      if (res < 0 && PyErr_ExceptionMatches(PyExc_KeyError))
-         PyErr_SetObject(PyExc_AttributeError, name);
+         PyErr_Format(PyExc_AttributeError,
+                      "'%.100s' object has no attribute '%U'",
+                      tp->tp_name, name);

-             PyErr_SetObject(PyExc_AttributeError, name);
+             PyErr_Format(PyExc_AttributeError,
+                          "'%.100s' object has no attribute '%U'",
+                          Py_TYPE(obj)->tp_name, name);

-     if (res < 0 && PyErr_ExceptionMatches(PyExc_KeyError))
-         PyErr_SetObject(PyExc_AttributeError, name);
+     if (res < 0 && PyErr_ExceptionMatches(PyExc_KeyError)) {
+         if (PyType_IsSubtype(tp, &PyType_Type)) {
+             PyErr_Format(PyExc_AttributeError,
+                          "type object '%.50s' has no attribute '%U'",
+                          ((PyTypeObject*)obj)->tp_name, name);
+         }
+         else {
+             PyErr_Format(PyExc_AttributeError,
+                          "'%.100s' object has no attribute '%U'",
+                          tp->tp_name, name);
+         }
+     }