diff --git a/notebook/serverextensions.py b/notebook/serverextensions.py
index c1e73de5e..de5838258 100644
--- a/notebook/serverextensions.py
+++ b/notebook/serverextensions.py
@@ -12,8 +12,8 @@ import sys
 from jupyter_core.paths import jupyter_config_path
 from ._version import __version__
 from .nbextensions import (
-    BaseNBExtensionApp, ToggleNBExtensionApp, _get_config_dir, _read_config_data,
-    _write_config_data, GREEN_ENABLED, RED_DISABLED
+    BaseNBExtensionApp, ToggleNBExtensionApp, _get_config_dir,
+    GREEN_ENABLED, RED_DISABLED
 )
 
 from traitlets import Bool
diff --git a/notebook/static/base/js/utils.js b/notebook/static/base/js/utils.js
index 8a1fa42c6..4ce55278d 100644
--- a/notebook/static/base/js/utils.js
+++ b/notebook/static/base/js/utils.js
@@ -842,7 +842,7 @@ define([
     var format_datetime = function(date) {
         var text = moment(date).fromNow();
         return text === 'a few seconds ago' ? 'seconds ago' : text;
-    }
+    };
 
     var datetime_sort_helper = function(a, b, order) {
         if (moment(a).isBefore(moment(b))) {
@@ -852,7 +852,7 @@ define([
         } else {
             return (order == 1) ? 1 : -1;
         }
-    }
+    };
 
     var utils = {
         load_extension: load_extension,
diff --git a/notebook/static/notebook/js/main.js b/notebook/static/notebook/js/main.js
index 1630dec32..b800d6f00 100644
--- a/notebook/static/notebook/js/main.js
+++ b/notebook/static/notebook/js/main.js
@@ -93,7 +93,7 @@ require([
     var save_widget = new savewidget.SaveWidget('span#save_widget', {
         events: events,
         keyboard_manager: keyboard_manager});
-    acts.extend_env({save_widget:save_widget})
+    acts.extend_env({save_widget:save_widget});
     var contents = new contentsModule.Contents({
           base_url: common_options.base_url,
           common_config: common_config
diff --git a/notebook/static/terminal/js/main.js b/notebook/static/terminal/js/main.js
index 7bac667e4..56a11fde5 100644
--- a/notebook/static/terminal/js/main.js
+++ b/notebook/static/terminal/js/main.js
@@ -35,7 +35,8 @@ require([
     var ws_url = location.protocol.replace('http', 'ws') + "//" + location.host
                                     + base_url + ws_path;
     
-    var header = $("#header")[0]
+    var header = $("#header")[0];
+
     function calculate_size() {
         var height = $(window).height() - header.offsetHeight;
         var width = $('#terminado-container').width();
diff --git a/notebook/tests/test_nbextensions.py b/notebook/tests/test_nbextensions.py
index 5da56b29c..1ebb5566f 100644
--- a/notebook/tests/test_nbextensions.py
+++ b/notebook/tests/test_nbextensions.py
@@ -6,7 +6,6 @@
 
 import glob
 import os
-import re
 import sys
 import tarfile
 import zipfile
@@ -51,7 +50,7 @@ class TestInstallNBExtension(TestCase):
 
     def setUp(self):
         self.tempdirs = []
-        src = self.src = self.tempdir()
+        self.src = self.tempdir()
         self.files = files = [
             pjoin(u'ƒile'),
             pjoin(u'∂ir', u'ƒile1'),
@@ -201,7 +200,7 @@ class TestInstallNBExtension(TestCase):
             install_nbextension(src)
             self.assert_installed(fname)
             dest = pjoin(self.system_nbext, fname)
-            old_mtime = os.stat(dest).st_mtime
+            os.stat(dest).st_mtime
             with open(src, 'w') as f:
                 f.write('overwrite')
             touch(src, mtime + 10)