Revert "pythongh-96844: Improve error message of list.remove (pythongh-106455)" (python#116956)

This reverts commit 217f47d.

Author: vstinner

Doc/library/doctest.rst

@@ -430,10 +430,10 @@ Simple example::
    >>> [1, 2, 3].remove(42)
    Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
-   ValueError: 42 is not in list
+   ValueError: list.remove(x): x not in list
 
-That doctest succeeds if :exc:`ValueError` is raised, with the ``42 is not in list``
-detail as shown.
+That doctest succeeds if :exc:`ValueError` is raised, with the ``list.remove(x):
+x not in list`` detail as shown.
 
 The expected output for an exception must start with a traceback header, which
 may be either of the following two lines, indented the same as the first line of

Lib/test/test_xml_etree.py

@@ -329,7 +329,7 @@ def test_simpleops(self):
         self.serialize_check(element, '<tag key="value" />') # 5
         with self.assertRaises(ValueError) as cm:
             element.remove(subelement)
-        self.assertIn('not in list', str(cm.exception))
+        self.assertEqual(str(cm.exception), 'list.remove(x): x not in list')
         self.serialize_check(element, '<tag key="value" />') # 6
         element[0:0] = [subelement, subelement, subelement]
         self.serialize_check(element[1], '<subtag />')

Objects/listobject.c

@@ -3194,7 +3194,7 @@ list_remove_impl(PyListObject *self, PyObject *value)
         else if (cmp < 0)
             return NULL;
     }
-    PyErr_Format(PyExc_ValueError, "%R is not in list", value);
+    PyErr_SetString(PyExc_ValueError, "list.remove(x): x not in list");
     return NULL;
 }