diff --git a/python/psi-api/src/com/jetbrains/python/psi/PyClass.java b/python/psi-api/src/com/jetbrains/python/psi/PyClass.java
index bb0eb8d5d682..5c4c08b4bbcb 100644
--- a/python/psi-api/src/com/jetbrains/python/psi/PyClass.java
+++ b/python/psi-api/src/com/jetbrains/python/psi/PyClass.java
@@ -23,6 +23,7 @@ import java.util.List;
 public interface PyClass extends PsiNameIdentifierOwner, PyStatement, NameDefiner, PyDocStringOwner, StubBasedPsiElement<PyClassStub>,
                                  ScopeOwner, PyDecoratable, PyTypedElement {
   ArrayFactory<PyClass> ARRAY_FACTORY = new ArrayFactory<PyClass>() {
+    @NotNull
     @Override
     public PyClass[] create(int count) {
       return new PyClass[count];
diff --git a/python/psi-api/src/com/jetbrains/python/psi/PyFunction.java b/python/psi-api/src/com/jetbrains/python/psi/PyFunction.java
index d303851848e9..5d125c7f5ff0 100644
--- a/python/psi-api/src/com/jetbrains/python/psi/PyFunction.java
+++ b/python/psi-api/src/com/jetbrains/python/psi/PyFunction.java
@@ -8,6 +8,7 @@ import com.intellij.util.ArrayFactory;
 import com.jetbrains.python.codeInsight.controlflow.ScopeOwner;
 import com.jetbrains.python.psi.stubs.PyFunctionStub;
 import com.jetbrains.python.psi.types.PyType;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 /**
@@ -22,6 +23,7 @@ extends
 
   PyFunction[] EMPTY_ARRAY = new PyFunction[0];
   ArrayFactory<PyFunction> ARRAY_FACTORY = new ArrayFactory<PyFunction>() {
+    @NotNull
     @Override
     public PyFunction[] create(int count) {
       return new PyFunction[count];
diff --git a/python/src/com/jetbrains/python/psi/impl/PyFromImportStatementImpl.java b/python/src/com/jetbrains/python/psi/impl/PyFromImportStatementImpl.java
index 45877d1cfd57..f887dece66af 100644
--- a/python/src/com/jetbrains/python/psi/impl/PyFromImportStatementImpl.java
+++ b/python/src/com/jetbrains/python/psi/impl/PyFromImportStatementImpl.java
@@ -75,6 +75,7 @@ public class PyFromImportStatementImpl extends PyBaseElementImpl<PyFromImportSta
     final PyFromImportStatementStub stub = getStub();
     if (stub != null) {
       return stub.getChildrenByType(PyElementTypes.IMPORT_ELEMENT, new ArrayFactory<PyImportElement>() {
+        @NotNull
         public PyImportElement[] create(int count) {
           return new PyImportElement[count];
         }
@@ -182,7 +183,7 @@ public class PyFromImportStatementImpl extends PyBaseElementImpl<PyFromImportSta
       ASTNode comma = PyElementGenerator.getInstance(getProject()).createComma();
       super.addInternal(comma, comma, prevNode, false);
     }
-    
+
     return result;
   }
 
diff --git a/python/src/com/jetbrains/python/psi/impl/PyImportStatementImpl.java b/python/src/com/jetbrains/python/psi/impl/PyImportStatementImpl.java
index 079ab213f9e0..c37d921c2cc7 100644
--- a/python/src/com/jetbrains/python/psi/impl/PyImportStatementImpl.java
+++ b/python/src/com/jetbrains/python/psi/impl/PyImportStatementImpl.java
@@ -32,6 +32,7 @@ public class PyImportStatementImpl extends PyBaseElementImpl<PyImportStatementSt
     final PyImportStatementStub stub = getStub();
     if (stub != null) {
       return stub.getChildrenByType(PyElementTypes.IMPORT_ELEMENT, new ArrayFactory<PyImportElement>() {
+        @NotNull
         public PyImportElement[] create(int count) {
           return new PyImportElement[count];
         }