diff --git a/python/src/com/jetbrains/python/psi/PyUtil.java b/python/src/com/jetbrains/python/psi/PyUtil.java
index a0bdbff59ac7..6cdce0a5a0e9 100644
--- a/python/src/com/jetbrains/python/psi/PyUtil.java
+++ b/python/src/com/jetbrains/python/psi/PyUtil.java
@@ -9,7 +9,6 @@ import com.intellij.ide.fileTemplates.FileTemplate;
 import com.intellij.ide.fileTemplates.FileTemplateManager;
 import com.intellij.lang.ASTFactory;
 import com.intellij.lang.ASTNode;
-import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.extensions.Extensions;
 import com.intellij.openapi.module.Module;
 import com.intellij.openapi.module.ModuleUtil;
@@ -38,6 +37,7 @@ import com.intellij.util.containers.HashSet;
 import com.jetbrains.python.PyBundle;
 import com.jetbrains.python.PyNames;
 import com.jetbrains.python.PyTokenTypes;
+import com.jetbrains.python.codeInsight.controlflow.ScopeOwner;
 import com.jetbrains.python.codeInsight.dataflow.scope.ScopeUtil;
 import com.jetbrains.python.codeInsight.stdlib.PyNamedTupleType;
 import com.jetbrains.python.documentation.EpydocUtil;
@@ -437,29 +437,23 @@ public class PyUtil {
     if (!(target instanceof PyTargetExpression)) {
       return false;
     }
-    PyFunction method = PsiTreeUtil.getParentOfType(target, PyFunction.class);
-    if (method == null || method.getContainingClass() == null) {
-      return false;
+    final ScopeOwner owner = ScopeUtil.getScopeOwner(target);
+    if (owner instanceof PyFunction) {
+      final PyFunction method = (PyFunction)owner;
+      if (method.getContainingClass() != null) {
+        final PyParameter[] params = method.getParameterList().getParameters();
+        if (params.length > 0) {
+          final PyTargetExpression targetExpr = (PyTargetExpression)target;
+          final PyExpression qualifier = targetExpr.getQualifier();
+          return qualifier != null && qualifier.getText().equals(params[0].getName());
+        }
+      }
     }
-    final PyParameter[] params = method.getParameterList().getParameters();
-    if (params.length == 0) {
-      return false;
-    }
-    final PyTargetExpression targetExpr = (PyTargetExpression)target;
-    PyExpression qualifier = targetExpr.getQualifier();
-    return qualifier != null && qualifier.getText().equals(params[0].getName());
+    return false;
   }
 
   public static boolean isClassAttribute(PsiElement element) {
-    PyAssignmentStatement statement = PsiTreeUtil.getParentOfType(element, PyAssignmentStatement.class);
-    if (statement == null) {
-      return false;
-    }
-    PyStatementList stmtList = PsiTreeUtil.getParentOfType(statement, PyStatementList.class);
-    if (stmtList == null || !(stmtList.getParent() instanceof PyClass)) {
-      return false;
-    }
-    return PsiTreeUtil.isAncestor(statement.getLeftHandSideExpression(), element, false);
+    return element instanceof PyTargetExpression && ScopeUtil.getScopeOwner(element) instanceof PyClass;
   }
 
   public static boolean isDocString(PyExpression expression) {
diff --git a/python/src/com/jetbrains/python/psi/impl/PyClassImpl.java b/python/src/com/jetbrains/python/psi/impl/PyClassImpl.java
index 5856cb7a5a44..d7816af54147 100644
--- a/python/src/com/jetbrains/python/psi/impl/PyClassImpl.java
+++ b/python/src/com/jetbrains/python/psi/impl/PyClassImpl.java
@@ -17,6 +17,7 @@ import com.intellij.util.containers.ContainerUtil;
 import com.jetbrains.python.*;
 import com.jetbrains.python.codeInsight.controlflow.ControlFlowCache;
 import com.jetbrains.python.codeInsight.controlflow.ScopeOwner;
+import com.jetbrains.python.codeInsight.dataflow.scope.ScopeUtil;
 import com.jetbrains.python.psi.*;
 import com.jetbrains.python.psi.resolve.PyResolveContext;
 import com.jetbrains.python.psi.resolve.PyResolveUtil;
@@ -1078,7 +1079,7 @@ public class PyClassImpl extends PyPresentableElementImpl<PyClassStub> implement
   @NotNull
   @Override
   public SearchScope getUseScope() {
-    final ScopeOwner scopeOwner = PsiTreeUtil.getParentOfType(this, ScopeOwner.class);
+    final ScopeOwner scopeOwner = ScopeUtil.getScopeOwner(this);
     if (scopeOwner instanceof PyFunction) {
       return new LocalSearchScope(scopeOwner);
     }
diff --git a/python/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java b/python/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java
index 51a444988de4..89b57c320d51 100644
--- a/python/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java
+++ b/python/src/com/jetbrains/python/psi/impl/PyFunctionImpl.java
@@ -21,6 +21,7 @@ import com.jetbrains.python.PyTokenTypes;
 import com.jetbrains.python.PythonDocStringFinder;
 import com.jetbrains.python.codeInsight.controlflow.ControlFlowCache;
 import com.jetbrains.python.codeInsight.controlflow.ScopeOwner;
+import com.jetbrains.python.codeInsight.dataflow.scope.ScopeUtil;
 import com.jetbrains.python.documentation.StructuredDocString;
 import com.jetbrains.python.psi.*;
 import com.jetbrains.python.psi.resolve.QualifiedNameFinder;
@@ -505,7 +506,7 @@ public class PyFunctionImpl extends PyPresentableElementImpl<PyFunctionStub> imp
   @NotNull
   @Override
   public SearchScope getUseScope() {
-    final ScopeOwner scopeOwner = PsiTreeUtil.getParentOfType(this, ScopeOwner.class);
+    final ScopeOwner scopeOwner = ScopeUtil.getScopeOwner(this);
     if (scopeOwner instanceof PyFunction) {
       return new LocalSearchScope(scopeOwner);
     }
diff --git a/python/src/com/jetbrains/python/psi/impl/references/PyReferenceImpl.java b/python/src/com/jetbrains/python/psi/impl/references/PyReferenceImpl.java
index 521f0e2e7f67..45ef257c07b3 100644
--- a/python/src/com/jetbrains/python/psi/impl/references/PyReferenceImpl.java
+++ b/python/src/com/jetbrains/python/psi/impl/references/PyReferenceImpl.java
@@ -419,10 +419,14 @@ public class PyReferenceImpl implements PsiReferenceEx, PsiPolyVariantReference
     return element;
   }
 
-  private static boolean isGlobal(PsiElement anchor, String name) {
-    final ScopeOwner owner = ScopeUtil.getDeclarationScopeOwner(anchor, name);
-    if (owner != null) {
-      return ControlFlowCache.getScope(owner).isGlobal(name);
+  private static boolean isGlobal(PsiElement element, String name) {
+    final ScopeOwner scopeOwner = ScopeUtil.getScopeOwner(element);
+    if (scopeOwner instanceof PyFile) {
+      return true;
+    }
+    final ScopeOwner declarationScopeOwner = ScopeUtil.getDeclarationScopeOwner(element, name);
+    if (declarationScopeOwner != null) {
+      return ControlFlowCache.getScope(declarationScopeOwner).isGlobal(name);
     }
     return false;
   }
@@ -535,15 +539,16 @@ public class PyReferenceImpl implements PsiReferenceEx, PsiPolyVariantReference
   private boolean resolvesToSameGlobal(PsiElement element, String elementName, ScopeOwner ourScopeOwner, ScopeOwner theirScopeOwner,
                                        PsiElement resolveResult) {
     // Handle situations when there is no top-level declaration for globals and transitive resolve doesn't help
-    final boolean ourIsGlobal = ControlFlowCache.getScope(ourScopeOwner).isGlobal(elementName);
-    final boolean theirIsGlobal = ControlFlowCache.getScope(theirScopeOwner).isGlobal(elementName);
     final PsiFile ourFile = getElement().getContainingFile();
     final PsiFile theirFile = element.getContainingFile();
-
-    if (ourIsGlobal && theirIsGlobal && ourFile == theirFile) {
-      return true;
+    if (ourFile == theirFile) {
+      final boolean ourIsGlobal = ControlFlowCache.getScope(ourScopeOwner).isGlobal(elementName);
+      final boolean theirIsGlobal = ControlFlowCache.getScope(theirScopeOwner).isGlobal(elementName);
+      if (ourIsGlobal && theirIsGlobal) {
+        return true;
+      }
     }
-    if (theirIsGlobal && ScopeUtil.getScopeOwner(resolveResult) == ourFile) {
+    if (ScopeUtil.getScopeOwner(resolveResult) == ourFile && ControlFlowCache.getScope(theirScopeOwner).isGlobal(elementName)) {
       return true;
     }
     return false;
diff --git a/python/src/com/jetbrains/python/psi/resolve/CompletionVariantsProcessor.java b/python/src/com/jetbrains/python/psi/resolve/CompletionVariantsProcessor.java
index 894fe51f622e..8c3ca5edb3f5 100644
--- a/python/src/com/jetbrains/python/psi/resolve/CompletionVariantsProcessor.java
+++ b/python/src/com/jetbrains/python/psi/resolve/CompletionVariantsProcessor.java
@@ -54,7 +54,7 @@ public class CompletionVariantsProcessor extends VariantsProcessor {
         final String params = StringUtil.join(parameterList.getParameters(), new Function<PyParameter, String>() {
           @Override
           public String fun(PyParameter pyParameter) {
-            return pyParameter.getText();
+            return pyParameter.getName();
           }
         }, ", ");
         item = item.withTailText("(" + params + ")");