Fix remaining issues with dict completions

jedi/inference/value/instance.py

@@ -355,7 +355,22 @@ class TreeInstance(_BaseTreeInstance):
         return self._get_annotated_class_object() or self.class_value
 
     def get_key_values(self):
-        return NO_VALUES
+        values = NO_VALUES
+        if self.array_type == 'dict':
+            for i, (key, instance) in enumerate(self._arguments.unpack()):
+                if key is None and i == 0:
+                    values |= ValueSet.from_sets(
+                        v.get_key_values()
+                        for v in instance.infer()
+                        if v.array_type == 'dict'
+                    )
+                if key:
+                    values |= ValueSet([compiled.create_simple_object(
+                        self.inference_state,
+                        key,
+                    )])
+
+        return values
 
     def py__simple_getitem__(self, index):
         if self.array_type == 'dict':