added return type annotation completion for method overriding

python/src/com/jetbrains/python/codeInsight/completion/PySuperMethodCompletionContributor.java

@@ -66,6 +66,9 @@ public class PySuperMethodCompletionContributor extends CompletionContributor {
                  for (PyFunction superMethod : ancestor.getMethods()) {
                    if (!seenNames.contains(superMethod.getName())) {
                      String text = superMethod.getName() + superMethod.getParameterList().getText();
+                     if (languageLevel.isAtLeast(LanguageLevel.PYTHON35) && superMethod.getAnnotation() != null) {
+                       text += " " + superMethod.getAnnotation().getText();
+                     }
                      LookupElementBuilder element = LookupElementBuilder.create(text);
                      result.addElement(TailTypeDecorator.withTail(element, TailType.CASE_COLON));
                      seenNames.add(superMethod.getName());

python/testData/completion/superMethodWithAnnotation.after.py

@@ -0,0 +1,7 @@
+class Parent:
+    def overridable_method(param: str) -> Dict[str, str]:
+        pass
+
+
+class Child(Parent):
+    def overridable_method(param: str) -> Dict[str, str]:

python/testData/completion/superMethodWithAnnotation.py

@@ -0,0 +1,7 @@
+class Parent:
+    def overridable_method(param: str) -> Dict[str, str]:
+        pass
+
+
+class Child(Parent):
+    def over<caret>

python/testSrc/com/jetbrains/python/PythonCompletionTest.java

@@ -314,6 +314,10 @@ public class PythonCompletionTest extends PyTestCase {
     doTest();
   }
 
+  public void testSuperMethodWithAnnotation() {
+    runWithLanguageLevel(LanguageLevel.PYTHON35, this::doTest);
+  }
+
   public void testLocalVarInDictKey() {  // PY-2558
     doTest();
   }