Fix an issue with a type var lookups

jedi/evaluate/context/typing.py

@@ -479,7 +479,7 @@ class _AbstractAnnotatedClass(ClassContext):
                 continue  # These are not relevant for this search.
 
             if node.type == 'atom_expr':
-                trailer = node.children[1]
+                trailer = node.children[-1]
                 if trailer.type == 'trailer' and trailer.children[0] == '[':
                     for subscript_node in self._unpack_subscriptlist(trailer.children[1]):
                         type_var_set = self.parent_context.eval_node(subscript_node)

test/completion/pep0484_typing.py

@@ -305,3 +305,16 @@ from typing import Union as U
 def union4(x: U[int, str]):
     #? int() str()
     x
+
+
+TYPE_VAR = typing.TypeVar('TYPE_VAR')
+
+
+class WithTypeVar(typing.Generic[TYPE_VAR]):
+    def lala(self) -> TYPE_VAR:
+        ...
+
+
+def maaan(p: WithTypeVar[int]):
+    #? int()
+    p.lala()