diff --git a/python/src/com/jetbrains/python/codeInsight/controlflow/ReadWriteInstruction.java b/python/src/com/jetbrains/python/codeInsight/controlflow/ReadWriteInstruction.java
index 5b343f1a30e3..cbc25a83821a 100644
--- a/python/src/com/jetbrains/python/codeInsight/controlflow/ReadWriteInstruction.java
+++ b/python/src/com/jetbrains/python/codeInsight/controlflow/ReadWriteInstruction.java
@@ -20,24 +20,32 @@ public class ReadWriteInstruction extends InstructionImpl {
   };
 
   public enum ACCESS {
-    READ(true, false),
-    WRITE(false, true),
-    WRITETYPE(false, true),
-    READWRITE(true, true);
+    READ(true, false, false),
+    WRITE(false, true, false),
+    ASSERTTYPE(false, false, true),
+    READWRITE(true, true, false);
 
     private final boolean isWrite;
     private final boolean isRead;
+    private final boolean isAssertType;
 
-    ACCESS(boolean read, boolean write) {
+    ACCESS(boolean read, boolean write, boolean assertType) {
       isRead = read;
       isWrite = write;
+      isAssertType = assertType;
     }
-    public boolean isWriteAccess(){
+
+    public boolean isWriteAccess() {
       return isWrite;
     }
-    public boolean isReadAccess(){
+
+    public boolean isReadAccess() {
       return isRead;
     }
+
+    public boolean isAssertTypeAccess() {
+      return isAssertType;
+    }
   }
 
   private final String myName;
@@ -93,7 +101,7 @@ public class ReadWriteInstruction extends InstructionImpl {
                                                 final PsiElement element,
                                                 final String name,
                                                 final Function<TypeEvalContext, PyType> getType) {
-    return new ReadWriteInstruction(builder, element, name, ACCESS.WRITETYPE, getType);
+    return new ReadWriteInstruction(builder, element, name, ACCESS.ASSERTTYPE, getType);
   }
 
   @Nullable
diff --git a/python/src/com/jetbrains/python/refactoring/PyDefUseUtil.java b/python/src/com/jetbrains/python/refactoring/PyDefUseUtil.java
index 11e3d68ba3df..d30776bb26a5 100644
--- a/python/src/com/jetbrains/python/refactoring/PyDefUseUtil.java
+++ b/python/src/com/jetbrains/python/refactoring/PyDefUseUtil.java
@@ -50,7 +50,7 @@ public class PyDefUseUtil {
       final PsiElement element = instruction.getElement();
       final String name = elementName(element);
       final ReadWriteInstruction.ACCESS access = instruction.getAccess();
-      if (access.isWriteAccess() && Comparing.strEqual(name, var.getName())) {
+      if ((access.isWriteAccess() || access.isAssertTypeAccess()) && Comparing.strEqual(name, var.getName())) {
         result.add(instruction);
         return;
       }
diff --git a/python/testData/codeInsight/controlflow/assert.txt b/python/testData/codeInsight/controlflow/assert.txt
index 20e88ed71962..d30cedb2ef2e 100644
--- a/python/testData/codeInsight/controlflow/assert.txt
+++ b/python/testData/codeInsight/controlflow/assert.txt
@@ -5,6 +5,6 @@
 4(5) READ ACCESS: isinstance
 5(6) READ ACCESS: x
 6(7) READ ACCESS: int
-7(8) WRITETYPE ACCESS: s
-8(9) WRITETYPE ACCESS: x
+7(8) ASSERTTYPE ACCESS: s
+8(9) ASSERTTYPE ACCESS: x
 9() element: null
\ No newline at end of file
diff --git a/python/testData/codeInsight/controlflow/assignment2.txt b/python/testData/codeInsight/controlflow/assignment2.txt
index 4531c455bec4..a3f468d77dd4 100644
--- a/python/testData/codeInsight/controlflow/assignment2.txt
+++ b/python/testData/codeInsight/controlflow/assignment2.txt
@@ -4,7 +4,7 @@
 3(4) element: PyIfStatement
 4(5,10) READ ACCESS: sibling
 5(6) element: PyStatementList. Condition: sibling:true
-6(7) WRITETYPE ACCESS: sibling
+6(7) ASSERTTYPE ACCESS: sibling
 7(8) element: PyAssignmentStatement
 8(9) element: PySubscriptionExpression
 9(10) READ ACCESS: sibling
diff --git a/python/testData/codeInsight/controlflow/break.txt b/python/testData/codeInsight/controlflow/break.txt
index 4b74c0ae9cb5..f00c85098ebb 100644
--- a/python/testData/codeInsight/controlflow/break.txt
+++ b/python/testData/codeInsight/controlflow/break.txt
@@ -5,7 +5,7 @@
 4(5) element: PyIfStatement
 5(6,9) READ ACCESS: condition
 6(7) element: PyStatementList. Condition: condition:true
-7(8) WRITETYPE ACCESS: condition
+7(8) ASSERTTYPE ACCESS: condition
 8(10) element: PyBreakStatement
 9(1) element: PyPrintStatement
 10() element: null
\ No newline at end of file
diff --git a/python/testData/codeInsight/controlflow/continue.txt b/python/testData/codeInsight/controlflow/continue.txt
index 531e228f1682..0da087d6cfe7 100644
--- a/python/testData/codeInsight/controlflow/continue.txt
+++ b/python/testData/codeInsight/controlflow/continue.txt
@@ -5,7 +5,7 @@
 4(5) element: PyIfStatement
 5(6,9) READ ACCESS: condition
 6(7) element: PyStatementList. Condition: condition:true
-7(8) WRITETYPE ACCESS: condition
+7(8) ASSERTTYPE ACCESS: condition
 8(1) element: PyContinueStatement
 9(1) element: PyPrintStatement
 10() element: null
\ No newline at end of file
diff --git a/python/testData/codeInsight/controlflow/ifelsereturn.txt b/python/testData/codeInsight/controlflow/ifelsereturn.txt
index be3de5e39d0f..d0513796c26a 100644
--- a/python/testData/codeInsight/controlflow/ifelsereturn.txt
+++ b/python/testData/codeInsight/controlflow/ifelsereturn.txt
@@ -2,7 +2,7 @@
 1(2) element: PyIfStatement
 2(3,13) READ ACCESS: markup
 3(4) element: PyStatementList. Condition: markup:true
-4(5) WRITETYPE ACCESS: markup
+4(5) ASSERTTYPE ACCESS: markup
 5(6) element: PyTryExceptStatement
 6(7,9) element: PyTryPart
 7(8,9) element: PyReturnStatement
diff --git a/python/testData/codeInsight/controlflow/isinstance.txt b/python/testData/codeInsight/controlflow/isinstance.txt
index 3df94dabb153..f7459afa9508 100644
--- a/python/testData/codeInsight/controlflow/isinstance.txt
+++ b/python/testData/codeInsight/controlflow/isinstance.txt
@@ -6,7 +6,7 @@
 5(6) READ ACCESS: s
 6(7,12) READ ACCESS: basestring
 7(8) element: PyStatementList. Condition: (isinstance(s, basestring)):true
-8(9) WRITETYPE ACCESS: s
+8(9) ASSERTTYPE ACCESS: s
 9(10) element: PyAssignmentStatement
 10(11) READ ACCESS: s
 11(16) WRITE ACCESS: s2
diff --git a/python/testData/codeInsight/controlflow/manyifs.txt b/python/testData/codeInsight/controlflow/manyifs.txt
index 3206af0e248d..26d53adaacd0 100644
--- a/python/testData/codeInsight/controlflow/manyifs.txt
+++ b/python/testData/codeInsight/controlflow/manyifs.txt
@@ -17,7 +17,7 @@
 16(17) element: PyIfStatement
 17(18,25) READ ACCESS: bbb
 18(19) element: PyStatementList. Condition: bbb:true
-19(20) WRITETYPE ACCESS: bbb
+19(20) ASSERTTYPE ACCESS: bbb
 20(21) element: PyAssignmentStatement
 21(25) WRITE ACCESS: var
 22(23) element: PyElsePart. Condition: aa == bb:false
diff --git a/python/testData/codeInsight/controlflow/return.txt b/python/testData/codeInsight/controlflow/return.txt
index 1d310e3b16b1..00235aed635c 100644
--- a/python/testData/codeInsight/controlflow/return.txt
+++ b/python/testData/codeInsight/controlflow/return.txt
@@ -5,7 +5,7 @@
 4(5) element: PyIfStatement
 5(6,9) READ ACCESS: condition
 6(7) element: PyStatementList. Condition: condition:true
-7(8) WRITETYPE ACCESS: condition
+7(8) ASSERTTYPE ACCESS: condition
 8(10) element: PyReturnStatement
 9(1) element: PyPrintStatement
 10() element: null
\ No newline at end of file
diff --git a/python/testData/codeInsight/controlflow/sliceassignment.txt b/python/testData/codeInsight/controlflow/sliceassignment.txt
index 4531c455bec4..a3f468d77dd4 100644
--- a/python/testData/codeInsight/controlflow/sliceassignment.txt
+++ b/python/testData/codeInsight/controlflow/sliceassignment.txt
@@ -4,7 +4,7 @@
 3(4) element: PyIfStatement
 4(5,10) READ ACCESS: sibling
 5(6) element: PyStatementList. Condition: sibling:true
-6(7) WRITETYPE ACCESS: sibling
+6(7) ASSERTTYPE ACCESS: sibling
 7(8) element: PyAssignmentStatement
 8(9) element: PySubscriptionExpression
 9(10) READ ACCESS: sibling
diff --git a/python/testData/codeInsight/controlflow/tryfinally.txt b/python/testData/codeInsight/controlflow/tryfinally.txt
index c85cfbfe2a61..3409584f677d 100644
--- a/python/testData/codeInsight/controlflow/tryfinally.txt
+++ b/python/testData/codeInsight/controlflow/tryfinally.txt
@@ -12,7 +12,7 @@
 11(12) READ ACCESS: status
 12(13,27) READ ACCESS: None
 13(14) element: PyStatementList. Condition: status is not None:true
-14(15) WRITETYPE ACCESS: status
+14(15) ASSERTTYPE ACCESS: status
 15(16) element: PyPrintStatement
 16(27) READ ACCESS: status
 17(18) element: PyFinallyPart
@@ -20,7 +20,7 @@
 19(20) READ ACCESS: status
 20(21,25) READ ACCESS: None
 21(22) element: PyStatementList. Condition: status is not None:true
-22(23) WRITETYPE ACCESS: status
+22(23) ASSERTTYPE ACCESS: status
 23(24) element: PyPrintStatement
 24(25) READ ACCESS: status
 25(26) element: PyExpressionStatement