diff --git a/cms/djangoapps/contentstore/management/commands/tests/test_create_course.py b/cms/djangoapps/contentstore/management/commands/tests/test_create_course.py
index 92a61c8ebf..e388bfbd22 100644
--- a/cms/djangoapps/contentstore/management/commands/tests/test_create_course.py
+++ b/cms/djangoapps/contentstore/management/commands/tests/test_create_course.py
@@ -3,7 +3,7 @@ Unittests for creating a course in an chosen modulestore
 """
 from __future__ import absolute_import
 
-from StringIO import StringIO
+from six import StringIO
 
 import ddt
 import six
diff --git a/cms/djangoapps/contentstore/management/commands/tests/test_export_olx.py b/cms/djangoapps/contentstore/management/commands/tests/test_export_olx.py
index f4a70dce75..a508505fa3 100644
--- a/cms/djangoapps/contentstore/management/commands/tests/test_export_olx.py
+++ b/cms/djangoapps/contentstore/management/commands/tests/test_export_olx.py
@@ -7,7 +7,7 @@ from __future__ import absolute_import
 import shutil
 import tarfile
 import unittest
-from StringIO import StringIO
+from six import StringIO
 from tempfile import mkdtemp
 
 import ddt
diff --git a/cms/djangoapps/contentstore/management/commands/tests/test_git_export.py b/cms/djangoapps/contentstore/management/commands/tests/test_git_export.py
index 2362292fdf..6d8d30433d 100644
--- a/cms/djangoapps/contentstore/management/commands/tests/test_git_export.py
+++ b/cms/djangoapps/contentstore/management/commands/tests/test_git_export.py
@@ -7,7 +7,7 @@ from __future__ import absolute_import
 import copy
 import os
 import shutil
-import StringIO
+from six import StringIO
 import subprocess
 import unittest
 from uuid import uuid4
@@ -60,18 +60,18 @@ class TestGitExport(CourseTestCase):
         test output.
         """
         with self.assertRaisesRegexp(CommandError, 'Error: unrecognized arguments:*'):
-            call_command('git_export', 'blah', 'blah', 'blah', stderr=StringIO.StringIO())
+            call_command('git_export', 'blah', 'blah', 'blah', stderr=StringIO())
 
         with self.assertRaisesMessage(CommandError, 'Error: too few arguments'):
-            call_command('git_export', stderr=StringIO.StringIO())
+            call_command('git_export', stderr=StringIO())
 
         # Send bad url to get course not exported
         with self.assertRaisesRegexp(CommandError, six.text_type(GitExportError.URL_BAD)):
-            call_command('git_export', 'foo/bar/baz', 'silly', stderr=StringIO.StringIO())
+            call_command('git_export', 'foo/bar/baz', 'silly', stderr=StringIO())
 
         # Send bad course_id to get course not exported
         with self.assertRaisesRegexp(CommandError, six.text_type(GitExportError.BAD_COURSE)):
-            call_command('git_export', 'foo/bar:baz', 'silly', stderr=StringIO.StringIO())
+            call_command('git_export', 'foo/bar:baz', 'silly', stderr=StringIO())
 
     def test_error_output(self):
         """
diff --git a/cms/djangoapps/contentstore/views/tests/test_import_export.py b/cms/djangoapps/contentstore/views/tests/test_import_export.py
index 462fe67e0c..c2b4cb7e06 100644
--- a/cms/djangoapps/contentstore/views/tests/test_import_export.py
+++ b/cms/djangoapps/contentstore/views/tests/test_import_export.py
@@ -9,7 +9,7 @@ import logging
 import os
 import re
 import shutil
-import StringIO
+from six import StringIO
 import tarfile
 import tempfile
 from uuid import uuid4
@@ -574,7 +574,7 @@ class ExportTestCase(CourseTestCase):
         resp = self.client.get(output_url)
         self._verify_export_succeeded(resp)
 
-        buff = StringIO.StringIO(b"".join(resp.streaming_content))
+        buff = StringIO("".join(resp.streaming_content))
         return tarfile.open(fileobj=buff)
 
     def _verify_export_succeeded(self, resp):
diff --git a/cms/djangoapps/contentstore/views/tests/test_videos.py b/cms/djangoapps/contentstore/views/tests/test_videos.py
index 9d142adbb4..609e8db127 100644
--- a/cms/djangoapps/contentstore/views/tests/test_videos.py
+++ b/cms/djangoapps/contentstore/views/tests/test_videos.py
@@ -10,6 +10,7 @@ import re
 from contextlib import contextmanager
 from datetime import datetime
 from functools import wraps
+from six import StringIO
 
 import dateutil.parser
 import ddt
@@ -1416,7 +1417,7 @@ class VideoUrlsCsvTestCase(VideoUploadTestMixin, CourseTestCase):
             response["Content-Disposition"],
             u"attachment; filename={course}_video_urls.csv".format(course=self.course.id.course)
         )
-        response_reader = six.StringIO(response.content)
+        response_reader = StringIO(response.content)
         reader = csv.DictReader(response_reader, dialect=csv.excel)
         self.assertEqual(
             reader.fieldnames,
diff --git a/cms/lib/xblock/tagging/test.py b/cms/lib/xblock/tagging/test.py
index 781985470d..f0b9c5e034 100644
--- a/cms/lib/xblock/tagging/test.py
+++ b/cms/lib/xblock/tagging/test.py
@@ -6,7 +6,7 @@ from __future__ import absolute_import
 
 import json
 from datetime import datetime
-from StringIO import StringIO
+from six import StringIO
 
 import ddt
 import six
diff --git a/common/djangoapps/static_replace/test/test_static_replace.py b/common/djangoapps/static_replace/test/test_static_replace.py
index c8646fea66..ace36a09fe 100644
--- a/common/djangoapps/static_replace/test/test_static_replace.py
+++ b/common/djangoapps/static_replace/test/test_static_replace.py
@@ -3,7 +3,7 @@
 from __future__ import absolute_import, print_function
 
 import re
-from cStringIO import StringIO
+from six import StringIO
 from six.moves.urllib.parse import parse_qsl, urlparse, urlunparse
 
 import ddt
@@ -192,7 +192,9 @@ def test_static_paths_out(mock_modulestore, mock_storage):
     static_course_url = '/c4x/org/course/asset/LAlec04_controller.swf?csConfigFile=%2Fc4x%2Forg%2Fcourse%2Fasset%2FLAlec04_config.xml&name1=value1&name2=value2'
     raw_url = '/static/js/capa/protex/protex.nocache.js?raw'
     xblock_url = '/static/xblock/resources/babys_first.lil_xblock/public/images/pacifier.png'
+    # xss-lint: disable=python-wrap-html
     pre_text = 'EMBED src ="{}" xblock={} text <tag a="{}"/><div class="'.format(static_url, xblock_url, raw_url)
+    # xss-lint: disable=python-wrap-html
     post_text = 'EMBED src ="{}" xblock={} text <tag a="{}"/><div class="'.format(static_course_url, xblock_url, raw_url)
     static_paths = []
     assert replace_static_urls(pre_text, DATA_DIRECTORY, COURSE_KEY, static_paths_out=static_paths) == post_text
diff --git a/common/djangoapps/third_party_auth/management/commands/tests/test_remove_social_auth_users.py b/common/djangoapps/third_party_auth/management/commands/tests/test_remove_social_auth_users.py
index 71ba00683e..0358a3edec 100644
--- a/common/djangoapps/third_party_auth/management/commands/tests/test_remove_social_auth_users.py
+++ b/common/djangoapps/third_party_auth/management/commands/tests/test_remove_social_auth_users.py
@@ -6,7 +6,7 @@ from __future__ import absolute_import
 import sys
 import unittest
 from contextlib import contextmanager
-from StringIO import StringIO
+from six import StringIO
 from uuid import uuid4
 
 from django.conf import settings
diff --git a/common/djangoapps/track/management/tests/test_tracked_command.py b/common/djangoapps/track/management/tests/test_tracked_command.py
index 8339a708c9..11d722ac53 100644
--- a/common/djangoapps/track/management/tests/test_tracked_command.py
+++ b/common/djangoapps/track/management/tests/test_tracked_command.py
@@ -1,7 +1,7 @@
 from __future__ import absolute_import
 
 import json
-from StringIO import StringIO
+from six import StringIO
 
 from django.core.management import call_command
 from django.test import TestCase
diff --git a/common/lib/capa/capa/tests/test_responsetypes.py b/common/lib/capa/capa/tests/test_responsetypes.py
index b3a1f59215..c8a58558c0 100644
--- a/common/lib/capa/capa/tests/test_responsetypes.py
+++ b/common/lib/capa/capa/tests/test_responsetypes.py
@@ -11,7 +11,7 @@ import random
 import textwrap
 import unittest
 import zipfile
-from cStringIO import StringIO
+from six import StringIO
 from datetime import datetime
 
 import mock
diff --git a/lms/djangoapps/ccx/views.py b/lms/djangoapps/ccx/views.py
index 6773fdf953..b9144839ec 100644
--- a/lms/djangoapps/ccx/views.py
+++ b/lms/djangoapps/ccx/views.py
@@ -9,7 +9,7 @@ import functools
 import json
 import logging
 from copy import deepcopy
-from cStringIO import StringIO
+from six import StringIO
 
 import pytz
 import six
diff --git a/lms/djangoapps/courseware/management/commands/tests/test_dump_course.py b/lms/djangoapps/courseware/management/commands/tests/test_dump_course.py
index f0f14acf4f..a968c300a4 100644
--- a/lms/djangoapps/courseware/management/commands/tests/test_dump_course.py
+++ b/lms/djangoapps/courseware/management/commands/tests/test_dump_course.py
@@ -7,7 +7,7 @@ Tests for Django management commands
 from __future__ import absolute_import
 
 import json
-from StringIO import StringIO
+from six import StringIO
 
 import factory
 import six
diff --git a/lms/djangoapps/dashboard/git_import.py b/lms/djangoapps/dashboard/git_import.py
index 585cfd4a90..224e1c2aff 100644
--- a/lms/djangoapps/dashboard/git_import.py
+++ b/lms/djangoapps/dashboard/git_import.py
@@ -8,7 +8,7 @@ from __future__ import absolute_import
 import logging
 import os
 import re
-import StringIO
+from six import StringIO
 import subprocess
 
 import mongoengine
@@ -261,7 +261,7 @@ def add_repo(repo, rdir_in, branch=None):
     ret_git += u'{0}Branch: {1}'.format('   \n', branch)
 
     # Get XML logging logger and capture debug to parse results
-    output = StringIO.StringIO()
+    output = StringIO()
     import_log_handler = logging.StreamHandler(output)
     import_log_handler.setLevel(logging.DEBUG)
 
diff --git a/lms/djangoapps/dashboard/management/commands/tests/test_git_add_course.py b/lms/djangoapps/dashboard/management/commands/tests/test_git_add_course.py
index 3d15982bbd..d1ccd26226 100644
--- a/lms/djangoapps/dashboard/management/commands/tests/test_git_add_course.py
+++ b/lms/djangoapps/dashboard/management/commands/tests/test_git_add_course.py
@@ -6,7 +6,7 @@ from __future__ import absolute_import
 import logging
 import os
 import shutil
-import StringIO
+from six import StringIO
 import subprocess
 import unittest
 from uuid import uuid4
@@ -66,7 +66,7 @@ class TestGitAddCourse(SharedModuleStoreTestCase):
         Convenience function for testing command failures
         """
         with self.assertRaisesRegexp(CommandError, regex):
-            call_command('git_add_course', *args, stderr=StringIO.StringIO())
+            call_command('git_add_course', *args, stderr=StringIO())
 
     def test_command_args(self):
         """
@@ -203,7 +203,7 @@ class TestGitAddCourse(SharedModuleStoreTestCase):
             git_import.add_repo('file://{0}'.format(bare_repo), None, None)
 
         # Get logger for checking strings in logs
-        output = StringIO.StringIO()
+        output = StringIO()
         test_log_handler = logging.StreamHandler(output)
         test_log_handler.setLevel(logging.DEBUG)
         glog = git_import.log
diff --git a/lms/djangoapps/dashboard/sysadmin.py b/lms/djangoapps/dashboard/sysadmin.py
index e8baafaffb..69f9c83569 100644
--- a/lms/djangoapps/dashboard/sysadmin.py
+++ b/lms/djangoapps/dashboard/sysadmin.py
@@ -7,7 +7,7 @@ from __future__ import absolute_import
 import json
 import logging
 import os
-import StringIO
+from six import StringIO
 import subprocess
 
 import mongoengine
@@ -78,7 +78,7 @@ class SysadminDashboardView(TemplateView):
         data should be iterable and is used to stream object over http
         """
 
-        csv_file = StringIO.StringIO()
+        csv_file = StringIO()
         writer = csv.writer(csv_file, dialect='excel', quotechar='"',
                             quoting=csv.QUOTE_ALL)
 
@@ -293,7 +293,7 @@ class Courses(SysadminDashboardView):
         log.debug(u'Adding course using git repo %s', gitloc)
 
         # Grab logging output for debugging imports
-        output = StringIO.StringIO()
+        output = StringIO()
         import_log_handler = logging.StreamHandler(output)
         import_log_handler.setLevel(logging.DEBUG)
 
diff --git a/lms/djangoapps/instructor/views/api.py b/lms/djangoapps/instructor/views/api.py
index 60afef59e7..ac12af8673 100644
--- a/lms/djangoapps/instructor/views/api.py
+++ b/lms/djangoapps/instructor/views/api.py
@@ -14,7 +14,7 @@ import logging
 import random
 import re
 import string
-import StringIO
+from six import StringIO
 import time
 
 import six
@@ -1842,7 +1842,7 @@ def generate_registration_codes(request, course_id):
     invoice_attachment = render_to_string('emails/registration_codes_sale_invoice_attachment.txt', context)
 
     #send_mail(subject, message, from_address, recipient_list, fail_silently=False)
-    csv_file = StringIO.StringIO()
+    csv_file = StringIO()
     csv_writer = csv.writer(csv_file)
     for registration_code in registration_codes:
         full_redeem_code_url = 'http://{base_url}{redeem_code_url}'.format(
@@ -1867,7 +1867,7 @@ def generate_registration_codes(request, course_id):
         if pdf_file is not None:
             email.attach(u'Invoice.pdf', pdf_file.getvalue(), 'application/pdf')
         else:
-            file_buffer = StringIO.StringIO(_('pdf download unavailable right now, please contact support.'))
+            file_buffer = StringIO(_('pdf download unavailable right now, please contact support.'))
             email.attach(u'pdf_unavailable.txt', file_buffer.getvalue(), 'text/plain')
         email.send()
 
diff --git a/lms/djangoapps/instructor_task/tasks_helper/enrollments.py b/lms/djangoapps/instructor_task/tasks_helper/enrollments.py
index ba745c4caa..f23d3d6630 100644
--- a/lms/djangoapps/instructor_task/tasks_helper/enrollments.py
+++ b/lms/djangoapps/instructor_task/tasks_helper/enrollments.py
@@ -5,7 +5,7 @@ from __future__ import absolute_import
 
 import logging
 from datetime import datetime
-from StringIO import StringIO
+from six import StringIO
 from time import time
 
 from django.conf import settings
diff --git a/lms/djangoapps/instructor_task/tests/test_models.py b/lms/djangoapps/instructor_task/tests/test_models.py
index 1672ecc808..a953d48778 100644
--- a/lms/djangoapps/instructor_task/tests/test_models.py
+++ b/lms/djangoapps/instructor_task/tests/test_models.py
@@ -5,7 +5,7 @@ from __future__ import absolute_import
 
 import copy
 import time
-from cStringIO import StringIO
+from six import StringIO
 
 import boto
 from django.conf import settings
diff --git a/lms/djangoapps/program_enrollments/management/commands/tests/test_reset_enrollment_data.py b/lms/djangoapps/program_enrollments/management/commands/tests/test_reset_enrollment_data.py
index 8315bc660b..c35254e01d 100644
--- a/lms/djangoapps/program_enrollments/management/commands/tests/test_reset_enrollment_data.py
+++ b/lms/djangoapps/program_enrollments/management/commands/tests/test_reset_enrollment_data.py
@@ -5,7 +5,7 @@ from __future__ import absolute_import
 
 import sys
 from contextlib import contextmanager
-from StringIO import StringIO
+from six import StringIO
 from uuid import uuid4
 
 from django.core.management import call_command
diff --git a/lms/djangoapps/shoppingcart/tests/test_reports.py b/lms/djangoapps/shoppingcart/tests/test_reports.py
index 3153a18a08..8b5a42688e 100644
--- a/lms/djangoapps/shoppingcart/tests/test_reports.py
+++ b/lms/djangoapps/shoppingcart/tests/test_reports.py
@@ -5,7 +5,7 @@ Tests for the Shopping Cart Models
 from __future__ import absolute_import
 
 import datetime
-import StringIO
+from six import StringIO
 from textwrap import dedent
 
 import pytz
@@ -139,7 +139,7 @@ class ReportTypeTests(ModuleStoreTestCase):
         Tests that a generated purchase report CSV is as we expect
         """
         report = initialize_report("refund_report", self.now - self.FIVE_MINS, self.now + self.FIVE_MINS)
-        csv_file = StringIO.StringIO()
+        csv_file = StringIO()
         report.write_csv(csv_file)
         csv = csv_file.getvalue()
         csv_file.close()
@@ -148,14 +148,14 @@ class ReportTypeTests(ModuleStoreTestCase):
 
     def test_basic_cert_status_csv(self):
         report = initialize_report("certificate_status", self.now - self.FIVE_MINS, self.now + self.FIVE_MINS, 'A', 'Z')
-        csv_file = StringIO.StringIO()
+        csv_file = StringIO()
         report.write_csv(csv_file)
         csv = csv_file.getvalue()
         self.assertEqual(csv.replace('\r\n', '\n').strip(), self.CORRECT_CERT_STATUS_CSV.strip())
 
     def test_basic_uni_revenue_share_csv(self):
         report = initialize_report("university_revenue_share", self.now - self.FIVE_MINS, self.now + self.FIVE_MINS, 'A', 'Z')
-        csv_file = StringIO.StringIO()
+        csv_file = StringIO()
         report.write_csv(csv_file)
         csv = csv_file.getvalue()
         self.assertEqual(csv.replace('\r\n', '\n').strip(), self.CORRECT_UNI_REVENUE_SHARE_CSV.strip())
@@ -227,7 +227,7 @@ class ItemizedPurchaseReportTest(ModuleStoreTestCase):
         Tests that a generated purchase report CSV is as we expect
         """
         report = initialize_report("itemized_purchase_report", self.now - self.FIVE_MINS, self.now + self.FIVE_MINS)
-        csv_file = StringIO.StringIO()
+        csv_file = StringIO()
         report.write_csv(csv_file)
         csv = csv_file.getvalue()
         csv_file.close()
diff --git a/openedx/core/djangoapps/content/course_overviews/tests/test_course_overviews.py b/openedx/core/djangoapps/content/course_overviews/tests/test_course_overviews.py
index 722d1fe7e6..08dab713d4 100644
--- a/openedx/core/djangoapps/content/course_overviews/tests/test_course_overviews.py
+++ b/openedx/core/djangoapps/content/course_overviews/tests/test_course_overviews.py
@@ -6,7 +6,7 @@ from __future__ import absolute_import
 import datetime
 import itertools
 import math
-from cStringIO import StringIO
+from six import StringIO
 
 import ddt
 import mock
diff --git a/openedx/core/djangoapps/oauth_dispatch/management/commands/tests/test_generate_jwt_signing_key.py b/openedx/core/djangoapps/oauth_dispatch/management/commands/tests/test_generate_jwt_signing_key.py
index 24df11d066..fe9b4c395f 100644
--- a/openedx/core/djangoapps/oauth_dispatch/management/commands/tests/test_generate_jwt_signing_key.py
+++ b/openedx/core/djangoapps/oauth_dispatch/management/commands/tests/test_generate_jwt_signing_key.py
@@ -8,7 +8,7 @@ import os
 import sys
 import tempfile
 from contextlib import contextmanager
-from StringIO import StringIO
+from six import StringIO
 
 import ddt
 import yaml
diff --git a/openedx/tests/xblock_integration/test_recommender.py b/openedx/tests/xblock_integration/test_recommender.py
index 2bb6ac822f..3202392f4c 100644
--- a/openedx/tests/xblock_integration/test_recommender.py
+++ b/openedx/tests/xblock_integration/test_recommender.py
@@ -7,7 +7,7 @@ from __future__ import absolute_import
 
 import itertools
 import json
-import StringIO
+from six import StringIO
 import unittest
 from copy import deepcopy
 
@@ -650,11 +650,11 @@ class TestRecommenderFileUploading(TestRecommender):
         happens or is rejected as expected.
         """
         if 'magic_number' in test_case:
-            f_handler = StringIO.StringIO(test_case['magic_number'].decode('hex'))
+            f_handler = StringIO(test_case['magic_number'].decode('hex'))
         elif content is not None:
-            f_handler = StringIO.StringIO(json.dumps(content, sort_keys=True))
+            f_handler = StringIO(json.dumps(content, sort_keys=True))
         else:
-            f_handler = StringIO.StringIO('')
+            f_handler = StringIO('')
 
         f_handler.content_type = test_case['mimetypes']
         f_handler.name = 'file' + test_case['suffixes']
diff --git a/openedx/tests/xblock_integration/xblock_testcase.py b/openedx/tests/xblock_integration/xblock_testcase.py
index db5d67b2c1..5632e2e160 100644
--- a/openedx/tests/xblock_integration/xblock_testcase.py
+++ b/openedx/tests/xblock_integration/xblock_testcase.py
@@ -429,7 +429,7 @@ class XBlockTestCase(XBlockStudentTestCaseMixin,
             usage_id = self.xblocks[block_urlname].scope_ids.usage_id
             encoded_id = usage_id.replace(";_", "/")
         Followed by:
-            page_xml = defusedxml.ElementTree.parse(StringIO.StringIO(response_content))
+            page_xml = defusedxml.ElementTree.parse(StringIO(response_content))
             page_xml.find("//[@data-usage-id={usage}]".format(usage=encoded_id))
         or
             soup_html = BeautifulSoup(response_content, 'html.parser')
diff --git a/scripts/xsslint/tests/test_main.py b/scripts/xsslint/tests/test_main.py
index fd0a0eedca..ecdf3b854c 100644
--- a/scripts/xsslint/tests/test_main.py
+++ b/scripts/xsslint/tests/test_main.py
@@ -5,7 +5,7 @@ Tests for main.py
 from __future__ import absolute_import
 
 import re
-from StringIO import StringIO
+from six import StringIO
 from unittest import TestCase
 
 import mock