Fix a false positive for not-an-iterable in Pylint.

ChangeLog

@@ -85,6 +85,11 @@ Release date: TBA
 * Improve ``as_string()`` representation for ``TypeVar``, ``ParamSpec`` and ``TypeVarTuple`` nodes, as well as
   type parameter in ``ClassDef``, ``FuncDef`` and ``TypeAlias`` nodes (PEP 695).
 
+* Fix a false positive for ``not-an-iterable`` in an ``ExceptionGroup`` context.
+
+  Closes pylint-dev/pylint#8985
+  Closes pylint-dev/pylint#10558
+
 
 What's New in astroid 3.3.11?
 =============================

astroid/interpreter/objectmodel.py

@@ -770,6 +770,12 @@ def attr_text(self):
         return node_classes.Const("")
 
 
+class GroupExceptionInstanceModel(ExceptionInstanceModel):
+    @property
+    def attr_exceptions(self) -> nodes.Tuple:
+        return node_classes.Tuple(parent=self._instance)
+
+
 class OSErrorInstanceModel(ExceptionInstanceModel):
     @property
     def attr_filename(self):
@@ -804,6 +810,7 @@ def attr_object(self):
 
 BUILTIN_EXCEPTIONS = {
     "builtins.SyntaxError": SyntaxErrorInstanceModel,
+    "builtins.ExceptionGroup": GroupExceptionInstanceModel,
     "builtins.ImportError": ImportErrorInstanceModel,
     "builtins.UnicodeDecodeError": UnicodeDecodeErrorInstanceModel,
     # These are all similar to OSError in terms of attributes

tests/test_group_exceptions.py

@@ -12,6 +12,7 @@
     List,
     Name,
     Try,
+    Tuple,
     Uninferable,
     bases,
     extract_node,
@@ -21,6 +22,22 @@
 from astroid.nodes import Expr, Raise, TryStar
 
 
+@pytest.mark.skipif(not PY311_PLUS, reason="Requires Python 3.11 or higher")
+def test_group_exceptions_exceptions() -> None:
+    node = extract_node(
+        textwrap.dedent(
+            """
+        try:
+            raise ExceptionGroup('', [TypeError(), TypeError()])
+        except ExceptionGroup as eg:
+            eg.exceptions #@"""
+        )
+    )
+
+    inferred = node.inferred()[0]
+    assert isinstance(inferred, Tuple)
+
+
 @pytest.mark.skipif(not PY311_PLUS, reason="Requires Python 3.11 or higher")
 def test_group_exceptions() -> None:
     node = extract_node(