diff --git a/python/ipnb/intellij.python.ipnb.iml b/python/ipnb/intellij.python.ipnb.iml
index 2801cb4e8c61..9ff1f18562db 100644
--- a/python/ipnb/intellij.python.ipnb.iml
+++ b/python/ipnb/intellij.python.ipnb.iml
@@ -26,7 +26,6 @@
     </orderEntry>
     <orderEntry type="library" name="http-client" level="project" />
     <orderEntry type="module" module-name="intellij.python.configure" />
-    <orderEntry type="library" name="commons-lang2.6" level="project" />
     <orderEntry type="library" name="markdown4j" level="project" />
   </component>
 </module>
\ No newline at end of file
diff --git a/python/ipnb/src/org/jetbrains/plugins/ipnb/format/IpnbParser.java b/python/ipnb/src/org/jetbrains/plugins/ipnb/format/IpnbParser.java
index efaa2b49a075..068051bded15 100644
--- a/python/ipnb/src/org/jetbrains/plugins/ipnb/format/IpnbParser.java
+++ b/python/ipnb/src/org/jetbrains/plugins/ipnb/format/IpnbParser.java
@@ -1,3 +1,4 @@
+// Copyright 2000-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package org.jetbrains.plugins.ipnb.format;
 
 import com.google.common.collect.Lists;
@@ -20,7 +21,7 @@ import com.intellij.util.text.VersionComparatorUtil;
 import com.jetbrains.python.packaging.PyPackage;
 import com.jetbrains.python.packaging.PyPackageUtil;
 import com.jetbrains.python.sdk.PythonSdkType;
-import org.apache.commons.lang.math.NumberUtils;
+import org.apache.commons.lang3.math.NumberUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.plugins.ipnb.editor.panels.IpnbEditablePanel;
@@ -574,7 +575,7 @@ public class IpnbParser {
             if (codemirrorModeMap.containsKey("version")) {
 
               String version = (String)codemirrorModeMap.get("version");
-              if (NumberUtils.isNumber(version)) {
+              if (NumberUtils.isCreatable(version)) {
                 try {
                   codemirrorModeMap.put("version", Integer.parseInt(version));
                 }