diff --git a/cms/djangoapps/contentstore/features/courses.py b/cms/djangoapps/contentstore/features/courses.py
index 2640b5c233..cb7b85f076 100644
--- a/cms/djangoapps/contentstore/features/courses.py
+++ b/cms/djangoapps/contentstore/features/courses.py
@@ -1,5 +1,6 @@
 # pylint: disable=missing-docstring
 # pylint: disable=redefined-outer-name
+# pylint: disable=unused-argument
 
 from lettuce import world, step
 from common import *
@@ -33,7 +34,7 @@ def i_create_a_course(step):
     create_a_course()
 
 
-# pylint disable=unused-argument, invalid-name
+# pylint: disable=invalid-name
 @step('I click the course link in Studio Home$')
 def i_click_the_course_link_in_studio_home(step):
     course_css = 'a.course-link'
@@ -42,7 +43,11 @@ def i_click_the_course_link_in_studio_home(step):
 
 @step('I see an error about the length of the org/course/run tuple')
 def i_see_error_about_length(step):
-    assert world.css_has_text('#course_creation_error', 'The combined length of the organization, course number, and course run fields cannot be more than 65 characters.')
+    assert world.css_has_text(
+        '#course_creation_error',
+        'The combined length of the organization, course number, '
+        'and course run fields cannot be more than 65 characters.'
+    )
 
 ############ ASSERTIONS ###################
 
@@ -54,7 +59,6 @@ def courseware_page_has_loaded_in_studio(step):
 
 
 @step('I see the course listed in Studio Home$')
-# pylint disable=unused-argument
 def i_see_the_course_in_studio_home(step):
     course_css = 'h3.class-title'
     assert world.css_has_text(course_css, world.scenario_dict['COURSE'].display_name)
diff --git a/cms/djangoapps/contentstore/tests/test_libraries.py b/cms/djangoapps/contentstore/tests/test_libraries.py
index b2e748fd55..dc6d8b976d 100644
--- a/cms/djangoapps/contentstore/tests/test_libraries.py
+++ b/cms/djangoapps/contentstore/tests/test_libraries.py
@@ -67,6 +67,13 @@ class LibraryTestCase(ModuleStoreTestCase):
             **(other_settings or {})
         )
 
+    def _add_simple_content_block(self):
+        """ Adds simple HTML block to library """
+        return ItemFactory.create(
+            category="html", parent_location=self.library.location,
+            user_id=self.user.id, publish_item=False
+        )
+
     def _refresh_children(self, lib_content_block, status_code_expected=200):
         """
         Helper method: Uses the REST API to call the 'refresh_children' handler
@@ -74,7 +81,11 @@ class LibraryTestCase(ModuleStoreTestCase):
         """
         if 'user' not in lib_content_block.runtime._services:  # pylint: disable=protected-access
             lib_content_block.runtime._services['user'] = Mock(user_id=self.user.id)  # pylint: disable=protected-access
-        handler_url = reverse_usage_url('component_handler', lib_content_block.location, kwargs={'handler': 'refresh_children'})
+        handler_url = reverse_usage_url(
+            'component_handler',
+            lib_content_block.location,
+            kwargs={'handler': 'refresh_children'}
+        )
         response = self.client.ajax_post(handler_url)
         self.assertEqual(response.status_code, status_code_expected)
         return modulestore().get_item(lib_content_block.location)
@@ -128,7 +139,7 @@ class TestLibraries(LibraryTestCase):
         Test the 'max_count' property of LibraryContent blocks.
         """
         for _ in range(0, num_to_create):
-            ItemFactory.create(category="html", parent_location=self.library.location, user_id=self.user.id, publish_item=False)
+            self._add_simple_content_block()
 
         with modulestore().default_store(ModuleStoreEnum.Type.split):
             course = CourseFactory.create()
@@ -203,9 +214,9 @@ class TestLibraries(LibraryTestCase):
         """
         Test that the same block definition is used for the library and course[s]
         """
-        block1 = ItemFactory.create(category="html", parent_location=self.library.location, user_id=self.user.id, publish_item=False)
+        block1 = self._add_simple_content_block()
         def_id1 = block1.definition_locator.definition_id
-        block2 = ItemFactory.create(category="html", parent_location=self.library.location, user_id=self.user.id, publish_item=False)
+        block2 = self._add_simple_content_block()
         def_id2 = block2.definition_locator.definition_id
         self.assertNotEqual(def_id1, def_id2)
 
@@ -461,7 +472,10 @@ class TestLibraryAccess(LibraryTestCase):
     def _assert_cannot_create_library(self, org="org", library="libfail", expected_code=403):
         """ Ensure the current user is not able to create a library. """
         self.assertTrue(expected_code >= 300)
-        response = self.client.ajax_post(LIBRARY_REST_URL, {'org': org, 'library': library, 'display_name': "Irrelevant"})
+        response = self.client.ajax_post(
+            LIBRARY_REST_URL,
+            {'org': org, 'library': library, 'display_name': "Irrelevant"}
+        )
         self.assertEqual(response.status_code, expected_code)
         key = LibraryLocator(org=org, library=library)
         self.assertEqual(modulestore().get_library(key), None)
@@ -574,7 +588,7 @@ class TestLibraryAccess(LibraryTestCase):
         Test the read-only role (LibraryUserRole and its org-level equivalent)
         """
         # As staff user, add a block to self.library:
-        block = ItemFactory.create(category="html", parent_location=self.library.location, user_id=self.user.id, publish_item=False)
+        block = self._add_simple_content_block()
 
         # Login as a non_staff_user:
         self._login_as_non_staff_user()
@@ -650,7 +664,7 @@ class TestLibraryAccess(LibraryTestCase):
         from a library with (write, read, or no) access to a course with (write or no) access.
         """
         # As staff user, add a block to self.library:
-        block = ItemFactory.create(category="html", parent_location=self.library.location, user_id=self.user.id, publish_item=False)
+        block = self._add_simple_content_block()
         # And create a course:
         with modulestore().default_store(ModuleStoreEnum.Type.split):
             course = CourseFactory.create()
@@ -687,7 +701,7 @@ class TestLibraryAccess(LibraryTestCase):
         access to a course with (write or no) access.
         """
         # As staff user, add a block to self.library:
-        ItemFactory.create(category="html", parent_location=self.library.location, user_id=self.user.id, publish_item=False)
+        self._add_simple_content_block()
         # And create a course:
         with modulestore().default_store(ModuleStoreEnum.Type.split):
             course = CourseFactory.create()
@@ -702,7 +716,8 @@ class TestLibraryAccess(LibraryTestCase):
 
         # Try updating our library content block:
         lc_block = self._add_library_content_block(course, self.lib_key)
-        self._bind_module(lc_block, user=self.non_staff_user)  # We must use the CMS's module system in order to get permissions checks.
+        # We must use the CMS's module system in order to get permissions checks.
+        self._bind_module(lc_block, user=self.non_staff_user)
         lc_block = self._refresh_children(lc_block, status_code_expected=200 if expected_result else 403)
         self.assertEqual(len(lc_block.children), 1 if expected_result else 0)
 
@@ -822,7 +837,7 @@ class TestOverrides(LibraryTestCase):
         # Change the settings in the library version:
         self.problem.display_name = "X"
         self.problem.weight = 99
-        new_data_value = "<problem><p>We change the data as well to check that non-overriden fields do get updated.</p></problem>"
+        new_data_value = "<problem><p>Changed data to check that non-overriden fields *do* get updated.</p></problem>"
         self.problem.data = new_data_value
         modulestore().update_item(self.problem, self.user.id)
 
diff --git a/cms/djangoapps/contentstore/views/item.py b/cms/djangoapps/contentstore/views/item.py
index 57f1d59ca9..e390811096 100644
--- a/cms/djangoapps/contentstore/views/item.py
+++ b/cms/djangoapps/contentstore/views/item.py
@@ -169,7 +169,10 @@ def xblock_handler(request, usage_key_string):
 
             source_course = duplicate_source_usage_key.course_key
             dest_course = parent_usage_key.course_key
-            if not has_studio_write_access(request.user, dest_course) or not has_studio_read_access(request.user, source_course):
+            if (
+                    not has_studio_write_access(request.user, dest_course) or
+                    not has_studio_read_access(request.user, source_course)
+            ):
                 raise PermissionDenied()
 
             dest_usage_key = _duplicate_item(
@@ -252,6 +255,7 @@ def xblock_view_handler(request, usage_key_string, view_name):
                         'page_size': int(request.REQUEST.get('page_size', 0)),
                     }
             except ValueError:
+                # pylint: disable=too-many-format-args
                 return HttpResponse(
                     content="Couldn't parse paging parameters: enable_paging: "
                             "%s, page_number: %s, page_size: %s".format(
@@ -435,7 +439,9 @@ def _save_xblock(user, xblock, data=None, children_strings=None, metadata=None,
                         try:
                             value = field.from_json(value)
                         except ValueError as verr:
-                            reason = _("Invalid data ({details})").format(details=verr.message) if verr.message else _("Invalid data")
+                            reason = _("Invalid data")
+                            if verr.message:
+                                reason = _("Invalid data ({details})").format(details=verr.message)
                             return JsonResponse({"error": reason}, 400)
                         field.write_to(xblock, value)
 
@@ -544,7 +550,9 @@ def _create_item(request):
             )
             store.update_item(course, request.user.id)
 
-        return JsonResponse({"locator": unicode(created_block.location), "courseKey": unicode(created_block.location.course_key)})
+        return JsonResponse(
+            {"locator": unicode(created_block.location), "courseKey": unicode(created_block.location.course_key)}
+        )
 
 
 def _duplicate_item(parent_usage_key, duplicate_source_usage_key, user, display_name=None):
@@ -559,9 +567,11 @@ def _duplicate_item(parent_usage_key, duplicate_source_usage_key, user, display_
         category = dest_usage_key.block_type
 
         # Update the display name to indicate this is a duplicate (unless display name provided).
-        duplicate_metadata = {}  # Can't use own_metadata(), b/c it converts data for JSON serialization - not suitable for setting metadata of the new block
+        # Can't use own_metadata(), b/c it converts data for JSON serialization -
+        # not suitable for setting metadata of the new block
+        duplicate_metadata = {}
         for field in source_item.fields.values():
-            if (field.scope == Scope.settings and field.is_set_on(source_item)):
+            if field.scope == Scope.settings and field.is_set_on(source_item):
                 duplicate_metadata[field.name] = field.read_from(source_item)
         if display_name is not None:
             duplicate_metadata['display_name'] = display_name
@@ -746,7 +756,9 @@ def create_xblock_info(xblock, data=None, metadata=None, include_ancestor_info=F
     is_library_block = isinstance(xblock.location, LibraryUsageLocator)
     is_xblock_unit = is_unit(xblock, parent_xblock)
     # this should not be calculated for Sections and Subsections on Unit page or for library blocks
-    has_changes = modulestore().has_changes(xblock) if (is_xblock_unit or course_outline) and not is_library_block else None
+    has_changes = None
+    if (is_xblock_unit or course_outline) and not is_library_block:
+        has_changes = modulestore().has_changes(xblock)
 
     if graders is None:
         if not is_library_block:
diff --git a/cms/djangoapps/contentstore/views/library.py b/cms/djangoapps/contentstore/views/library.py
index 9aeb9c9b13..2bd433c83f 100644
--- a/cms/djangoapps/contentstore/views/library.py
+++ b/cms/djangoapps/contentstore/views/library.py
@@ -26,7 +26,9 @@ from xmodule.modulestore import ModuleStoreEnum
 from xmodule.modulestore.django import modulestore
 
 from .component import get_component_templates, CONTAINER_TEMPATES
-from student.auth import STUDIO_VIEW_USERS, STUDIO_EDIT_ROLES, get_user_permissions, has_studio_read_access, has_studio_write_access
+from student.auth import (
+    STUDIO_VIEW_USERS, STUDIO_EDIT_ROLES, get_user_permissions, has_studio_read_access, has_studio_write_access
+)
 from student.roles import CourseCreatorRole, CourseInstructorRole, CourseStaffRole, LibraryUserRole
 from student import auth
 from util.json_request import expect_json, JsonResponse, JsonResponseBadRequest
@@ -71,7 +73,10 @@ def _display_library(library_key_string, request):
         log.exception("Non-library key passed to content libraries API.")  # Should never happen due to url regex
         raise Http404  # This is not a library
     if not has_studio_read_access(request.user, library_key):
-        log.exception(u"User %s tried to access library %s without permission", request.user.username, unicode(library_key))
+        log.exception(
+            u"User %s tried to access library %s without permission",
+            request.user.username, unicode(library_key)
+        )
         raise PermissionDenied()
 
     library = modulestore().get_library(library_key)
@@ -80,7 +85,10 @@ def _display_library(library_key_string, request):
         raise Http404
 
     response_format = 'html'
-    if request.REQUEST.get('format', 'html') == 'json' or 'application/json' in request.META.get('HTTP_ACCEPT', 'text/html'):
+    if (
+            request.REQUEST.get('format', 'html') == 'json' or
+            'application/json' in request.META.get('HTTP_ACCEPT', 'text/html')
+    ):
         response_format = 'json'
 
     return library_blocks_view(library, request.user, response_format)
@@ -134,8 +142,8 @@ def _create_library(request):
     except InvalidKeyError as error:
         log.exception("Unable to create library - invalid key.")
         return JsonResponseBadRequest({
-            "ErrMsg": _("Unable to create library '{name}'.\n\n{err}").format(name=display_name, err=error.message)}
-        )
+            "ErrMsg": _("Unable to create library '{name}'.\n\n{err}").format(name=display_name, err=error.message)
+        })
     except DuplicateCourseError:
         log.exception("Unable to create library - one already exists with the same key.")
         return JsonResponseBadRequest({
@@ -203,7 +211,7 @@ def manage_library_users(request, library_key_string):
     if not isinstance(library_key, LibraryLocator):
         raise Http404  # This is not a library
     user_perms = get_user_permissions(request.user, library_key)
-    if not (user_perms & STUDIO_VIEW_USERS):
+    if not user_perms & STUDIO_VIEW_USERS:
         raise PermissionDenied()
     library = modulestore().get_library(library_key)
     if library is None:
diff --git a/cms/djangoapps/contentstore/views/tests/test_item.py b/cms/djangoapps/contentstore/views/tests/test_item.py
index 69898bfbe2..c322233319 100644
--- a/cms/djangoapps/contentstore/views/tests/test_item.py
+++ b/cms/djangoapps/contentstore/views/tests/test_item.py
@@ -1508,7 +1508,8 @@ class TestLibraryXBlockInfo(ModuleStoreTestCase):
             parent_location=self.library.location, category='vertical', user_id=user_id, publish_item=False
         )
         self.child_html = ItemFactory.create(
-            parent_location=self.vertical.location, category='html', display_name='Test HTML Child Block', user_id=user_id, publish_item=False
+            parent_location=self.vertical.location, category='html', display_name='Test HTML Child Block',
+            user_id=user_id, publish_item=False
         )
 
     def test_lib_xblock_info(self):
diff --git a/cms/djangoapps/contentstore/views/tests/test_library.py b/cms/djangoapps/contentstore/views/tests/test_library.py
index 0b0abe2e3b..7289022e8f 100644
--- a/cms/djangoapps/contentstore/views/tests/test_library.py
+++ b/cms/djangoapps/contentstore/views/tests/test_library.py
@@ -215,7 +215,10 @@ class UnitTestLibraries(ModuleStoreTestCase):
         self.assertNotIn(extra_user.username, response.content)
 
         # Now add extra_user to the library:
-        user_details_url = reverse_course_url('course_team_handler', library.location.library_key, kwargs={'email': extra_user.email})
+        user_details_url = reverse_course_url(
+            'course_team_handler',
+            library.location.library_key, kwargs={'email': extra_user.email}
+        )
         edit_response = self.client.ajax_post(user_details_url, {"role": LibraryUserRole.ROLE})
         self.assertIn(edit_response.status_code, (200, 204))
 
diff --git a/cms/djangoapps/contentstore/views/user.py b/cms/djangoapps/contentstore/views/user.py
index 812890a451..93a7c66a77 100644
--- a/cms/djangoapps/contentstore/views/user.py
+++ b/cms/djangoapps/contentstore/views/user.py
@@ -67,7 +67,7 @@ def _manage_users(request, course_key):
     """
     # check that logged in user has permissions to this item
     user_perms = get_user_permissions(request.user, course_key)
-    if not (user_perms & STUDIO_VIEW_USERS):
+    if not user_perms & STUDIO_VIEW_USERS:
         raise PermissionDenied()
 
     course_module = modulestore().get_course(course_key)
@@ -156,7 +156,8 @@ def _course_team_user(request, course_key, email):
         role = role_type(course_key)
         if role_type.ROLE == new_role:
             if (requester_perms & STUDIO_EDIT_ROLES) or (user.id == request.user.id and old_roles):
-                # User has STUDIO_EDIT_ROLES permission or is currently a member of a higher role, and is thus demoting themself
+                # User has STUDIO_EDIT_ROLES permission or
+                # is currently a member of a higher role, and is thus demoting themself
                 auth.add_users(request.user, role, user)
                 role_added = True
             else:
diff --git a/cms/urls.py b/cms/urls.py
index 81077120fc..ce46e77908 100644
--- a/cms/urls.py
+++ b/cms/urls.py
@@ -6,7 +6,9 @@ from ratelimitbackend import admin
 admin.autodiscover()
 
 # Pattern to match a course key or a library key
-COURSELIKE_KEY_PATTERN = r'(?P<course_key_string>({}|{}))'.format(r'[^/]+/[^/]+/[^/]+', r'[^/:]+:[^/+]+\+[^/+]+(\+[^/]+)?')
+COURSELIKE_KEY_PATTERN = r'(?P<course_key_string>({}|{}))'.format(
+    r'[^/]+/[^/]+/[^/]+', r'[^/:]+:[^/+]+\+[^/+]+(\+[^/]+)?'
+)
 # Pattern to match a library key only
 LIBRARY_KEY_PATTERN = r'(?P<library_key_string>library-v1:[^/+]+\+[^/+]+)'
 
diff --git a/common/djangoapps/student/auth.py b/common/djangoapps/student/auth.py
index 90b311e77e..a927bb5097 100644
--- a/common/djangoapps/student/auth.py
+++ b/common/djangoapps/student/auth.py
@@ -17,7 +17,7 @@ STUDIO_EDIT_ROLES = 8
 STUDIO_VIEW_USERS = 4
 STUDIO_EDIT_CONTENT = 2
 STUDIO_VIEW_CONTENT = 1
-# In addition to the above, one is always allowed to "demote" oneself to a lower role within a course, or remove oneself.
+# In addition to the above, one is always allowed to "demote" oneself to a lower role within a course, or remove oneself
 
 
 def has_access(user, role):
@@ -70,7 +70,7 @@ def get_user_permissions(user, course_key, org=None):
     if OrgStaffRole(org=org).has_user(user) or (course_key and has_access(user, CourseStaffRole(course_key))):
         return STUDIO_VIEW_USERS | STUDIO_EDIT_CONTENT | STUDIO_VIEW_CONTENT
     # Otherwise, for libraries, users can view only:
-    if (course_key and isinstance(course_key, LibraryLocator)):
+    if course_key and isinstance(course_key, LibraryLocator):
         if OrgLibraryUserRole(org=org).has_user(user) or has_access(user, LibraryUserRole(course_key)):
             return STUDIO_VIEW_USERS | STUDIO_VIEW_CONTENT
     return 0
diff --git a/common/djangoapps/terrain/ui_helpers.py b/common/djangoapps/terrain/ui_helpers.py
index f13811467a..2b5248a1ab 100644
--- a/common/djangoapps/terrain/ui_helpers.py
+++ b/common/djangoapps/terrain/ui_helpers.py
@@ -48,7 +48,7 @@ REQUIREJS_WAIT = {
         "js/base", "js/models/course", "js/models/location", "js/models/section"],
 
     # Dashboard
-    # pylint disable=anomalous-backslash-in-string
+    # pylint: disable=anomalous-backslash-in-string
     re.compile('^Studio Home \|'): [
         "js/sock", "gettext", "js/base",
         "jquery.ui", "coffee/src/main", "underscore"],
diff --git a/common/lib/xmodule/xmodule/capa_module.py b/common/lib/xmodule/xmodule/capa_module.py
index 47583d9706..b748b359f1 100644
--- a/common/lib/xmodule/xmodule/capa_module.py
+++ b/common/lib/xmodule/xmodule/capa_module.py
@@ -177,7 +177,7 @@ class CapaDescriptor(CapaFields, RawDescriptor):
     @property
     def problem_types(self):
         """ Low-level problem type introspection for content libraries filtering by problem type """
-        tree = etree.XML(self.data)
+        tree = etree.XML(self.data)  # pylint: disable=no-member
         registered_tags = responsetypes.registry.registered_tags()
         return set([node.tag for node in tree.iter() if node.tag in registered_tags])
 
diff --git a/common/lib/xmodule/xmodule/library_content_module.py b/common/lib/xmodule/xmodule/library_content_module.py
index 972919e2fa..e4c3252b37 100644
--- a/common/lib/xmodule/xmodule/library_content_module.py
+++ b/common/lib/xmodule/xmodule/library_content_module.py
@@ -20,7 +20,7 @@ from xmodule.validation import StudioValidationMessage, StudioValidation
 from xmodule.x_module import XModule, STUDENT_VIEW
 from xmodule.studio_editable import StudioEditableModule, StudioEditableDescriptor
 from .xml_module import XmlDescriptor
-from pkg_resources import resource_string
+from pkg_resources import resource_string  # pylint: disable=no-name-in-module
 
 
 # Make '_' a no-op so we can scrape strings
@@ -187,7 +187,8 @@ class LibraryContentFields(object):
         scope=Scope.settings,
     )
     selected = List(
-        # This is a list of (block_type, block_id) tuples used to record which random/first set of matching blocks was selected per user
+        # This is a list of (block_type, block_id) tuples used to record
+        # which random/first set of matching blocks was selected per user
         default=[],
         scope=Scope.user_state,
     )
@@ -296,7 +297,8 @@ class LibraryContentModule(LibraryContentFields, XModule, StudioEditableModule):
                     'display_name': self.display_name or self.url_name,
                 }))
                 self.render_children(context, fragment, can_reorder=False, can_add=False)
-        # else: When shown on a unit page, don't show any sort of preview - just the status of this block in the validation area.
+        # else: When shown on a unit page, don't show any sort of preview -
+        # just the status of this block in the validation area.
 
         # The following JS is used to make the "Update now" button work on the unit page and the container view:
         fragment.add_javascript_url(self.runtime.local_resource_url(self, 'public/js/library_content_edit.js'))
@@ -412,7 +414,8 @@ class LibraryContentDescriptor(LibraryContentFields, MakoModuleDescriptor, XmlDe
             if not self._validate_library_version(validation, lib_tools, version, library_key):
                 break
 
-        # Note: we assume refresh_children() has been called since the last time fields like source_libraries or capa_types were changed.
+        # Note: we assume refresh_children() has been called
+        # since the last time fields like source_libraries or capa_types were changed.
         matching_children_count = len(self.children)  # pylint: disable=no-member
         if matching_children_count == 0:
             self._set_validation_error_if_empty(
diff --git a/common/lib/xmodule/xmodule/library_tools.py b/common/lib/xmodule/xmodule/library_tools.py
index 4bdf51bdce..8f3c6d0cee 100644
--- a/common/lib/xmodule/xmodule/library_tools.py
+++ b/common/lib/xmodule/xmodule/library_tools.py
@@ -93,4 +93,5 @@ class LibraryToolsService(object):
             dest_block.source_libraries = new_libraries
             self.store.update_item(dest_block, user_id)
             dest_block.children = self.store.copy_from_template(source_blocks, dest_block.location, user_id)
-            # ^-- copy_from_template updates the children in the DB but we must also set .children here to avoid overwriting the DB again
+            # ^-- copy_from_template updates the children in the DB
+            # but we must also set .children here to avoid overwriting the DB again
diff --git a/common/lib/xmodule/xmodule/modulestore/split_mongo/split.py b/common/lib/xmodule/xmodule/modulestore/split_mongo/split.py
index 6c375d2dfc..c4d5d638e8 100644
--- a/common/lib/xmodule/xmodule/modulestore/split_mongo/split.py
+++ b/common/lib/xmodule/xmodule/modulestore/split_mongo/split.py
@@ -673,7 +673,8 @@ class SplitMongoModuleStore(SplitBulkWriteMixin, ModuleStoreWriteBase):
             new_module_data = {}
             for block_id in base_block_ids:
                 new_module_data = self.descendants(
-                    copy.deepcopy(system.course_entry.structure['blocks']),  # copy or our changes like setting 'definition_loaded' will affect the active bulk operation data
+                    # copy or our changes like setting 'definition_loaded' will affect the active bulk operation data
+                    copy.deepcopy(system.course_entry.structure['blocks']),
                     block_id,
                     depth,
                     new_module_data
@@ -2125,8 +2126,11 @@ class SplitMongoModuleStore(SplitBulkWriteMixin, ModuleStoreWriteBase):
             # Set of all descendent block IDs of dest_usage that are to be replaced:
             block_key = BlockKey(dest_usage.block_type, dest_usage.block_id)
             orig_descendants = set(self.descendants(dest_structure['blocks'], block_key, depth=None, descendent_map={}))
-            orig_descendants.remove(block_key)  # The descendants() method used above adds the block itself, which we don't consider a descendant.
-            new_descendants = self._copy_from_template(source_structures, source_keys, dest_structure, block_key, user_id)
+            # The descendants() method used above adds the block itself, which we don't consider a descendant.
+            orig_descendants.remove(block_key)
+            new_descendants = self._copy_from_template(
+                source_structures, source_keys, dest_structure, block_key, user_id
+            )
 
             # Update the edit info:
             dest_info = dest_structure['blocks'][block_key]
@@ -2144,7 +2148,10 @@ class SplitMongoModuleStore(SplitBulkWriteMixin, ModuleStoreWriteBase):
             self.update_structure(destination_course, dest_structure)
             self._update_head(destination_course, index_entry, destination_course.branch, dest_structure['_id'])
         # Return usage locators for all the new children:
-        return [destination_course.make_usage_key(*k) for k in dest_structure['blocks'][block_key]['fields']['children']]
+        return [
+            destination_course.make_usage_key(*k)
+            for k in dest_structure['blocks'][block_key]['fields']['children']
+        ]
 
     def _copy_from_template(self, source_structures, source_keys, dest_structure, new_parent_block_key, user_id):
         """
@@ -2184,10 +2191,13 @@ class SplitMongoModuleStore(SplitBulkWriteMixin, ModuleStoreWriteBase):
             new_block_info['defaults'] = new_block_info['fields']
 
             # <workaround>
-            # CAPA modules store their 'markdown' value (an alternate representation of their content) in Scope.settings rather than Scope.content :-/
+            # CAPA modules store their 'markdown' value (an alternate representation of their content)
+            # in Scope.settings rather than Scope.content :-/
             # markdown is a field that really should not be overridable - it fundamentally changes the content.
-            # capa modules also use a custom editor that always saves their markdown field to the metadata, even if it hasn't changed, which breaks our override system.
-            # So until capa modules are fixed, we special-case them and remove their markdown fields, forcing the inherited version to use XML only.
+            # capa modules also use a custom editor that always saves their markdown field to the metadata,
+            # even if it hasn't changed, which breaks our override system.
+            # So until capa modules are fixed, we special-case them and remove their markdown fields,
+            # forcing the inherited version to use XML only.
             if usage_key.block_type == 'problem' and 'markdown' in new_block_info['defaults']:
                 del new_block_info['defaults']['markdown']
             # </workaround>
@@ -2199,7 +2209,8 @@ class SplitMongoModuleStore(SplitBulkWriteMixin, ModuleStoreWriteBase):
             new_block_info['edit_info'] = existing_block_info.get('edit_info', {})
             new_block_info['edit_info']['previous_version'] = new_block_info['edit_info'].get('update_version', None)
             new_block_info['edit_info']['update_version'] = dest_structure['_id']
-            # Note we do not set 'source_version' - it's only used for copying identical blocks from draft to published as part of publishing workflow.
+            # Note we do not set 'source_version' - it's only used for copying identical blocks
+            # from draft to published as part of publishing workflow.
             # Setting it to the source_block_info structure version here breaks split_draft's has_changes() method.
             new_block_info['edit_info']['edited_by'] = user_id
             new_block_info['edit_info']['edited_on'] = datetime.datetime.now(UTC)
@@ -2208,7 +2219,9 @@ class SplitMongoModuleStore(SplitBulkWriteMixin, ModuleStoreWriteBase):
             children = source_block_info['fields'].get('children')
             if children:
                 children = [src_course_key.make_usage_key(child.type, child.id) for child in children]
-                new_blocks |= self._copy_from_template(source_structures, children, dest_structure, new_block_key, user_id)
+                new_blocks |= self._copy_from_template(
+                    source_structures, children, dest_structure, new_block_key, user_id
+                )
 
             new_blocks.add(new_block_key)
             # And add new_block_key to the list of new_parent_block_key's new children:
diff --git a/common/lib/xmodule/xmodule/modulestore/split_mongo/split_draft.py b/common/lib/xmodule/xmodule/modulestore/split_mongo/split_draft.py
index c651512c82..30fe251823 100644
--- a/common/lib/xmodule/xmodule/modulestore/split_mongo/split_draft.py
+++ b/common/lib/xmodule/xmodule/modulestore/split_mongo/split_draft.py
@@ -110,7 +110,8 @@ class DraftVersioningModuleStore(SplitMongoModuleStore, ModuleStoreDraftAndPubli
                     if usage_key.category in DIRECT_ONLY_CATEGORIES:
                         self.publish(usage_key.version_agnostic(), user_id, blacklist=EXCLUDE_ALL, **kwargs)
                         children = getattr(self.get_item(usage_key, **kwargs), "children", [])
-                        keys_to_check.extend(children)  # e.g. if usage_key is a chapter, it may have an auto-publish sequential child
+                        # e.g. if usage_key is a chapter, it may have an auto-publish sequential child
+                        keys_to_check.extend(children)
         return new_keys
 
     def update_item(self, descriptor, user_id, allow_not_found=False, force=False, **kwargs):
@@ -431,6 +432,7 @@ class DraftVersioningModuleStore(SplitMongoModuleStore, ModuleStoreDraftAndPubli
         pass
 
     def _get_head(self, xblock, branch):
+        """ Gets block at the head of specified branch """
         try:
             course_structure = self._lookup_course(xblock.location.course_key.for_branch(branch)).structure
         except ItemNotFoundError:
diff --git a/common/lib/xmodule/xmodule/modulestore/tests/test_split_copy_from_template.py b/common/lib/xmodule/xmodule/modulestore/tests/test_split_copy_from_template.py
index 3d73178644..bfdd7d0fea 100644
--- a/common/lib/xmodule/xmodule/modulestore/tests/test_split_copy_from_template.py
+++ b/common/lib/xmodule/xmodule/modulestore/tests/test_split_copy_from_template.py
@@ -28,12 +28,18 @@ class TestSplitCopyTemplate(MixedSplitTestCase):
         # Add a vertical with a capa child to the source library/course:
         vertical_block = self.make_block("vertical", source_container)
         problem_library_display_name = "Problem Library Display Name"
-        problem_block = self.make_block("problem", vertical_block, display_name=problem_library_display_name, markdown="Problem markdown here")
+        problem_block = self.make_block(
+            "problem", vertical_block, display_name=problem_library_display_name, markdown="Problem markdown here"
+        )
 
         if source_type == LibraryFactory:
-            source_container = self.store.get_library(source_container.location.library_key, remove_version=False, remove_branch=False)
+            source_container = self.store.get_library(
+                source_container.location.library_key, remove_version=False, remove_branch=False
+            )
         else:
-            source_container = self.store.get_course(source_container.location.course_key, remove_version=False, remove_branch=False)
+            source_container = self.store.get_course(
+                source_container.location.course_key, remove_version=False, remove_branch=False
+            )
 
         # Inherit the vertical and the problem from the library into the course:
         source_keys = [source_container.children[0]]
@@ -48,7 +54,8 @@ class TestSplitCopyTemplate(MixedSplitTestCase):
         problem_block_course = self.store.get_item(vertical_block_course.children[0])
         self.assertEqual(problem_block_course.display_name, problem_library_display_name)
 
-        # Check that when capa modules are copied, their "markdown" fields (Scope.settings) are removed. (See note in split.py:copy_from_template())
+        # Check that when capa modules are copied, their "markdown" fields (Scope.settings) are removed.
+        # (See note in split.py:copy_from_template())
         self.assertIsNotNone(problem_block.markdown)
         self.assertIsNone(problem_block_course.markdown)
 
@@ -59,7 +66,8 @@ class TestSplitCopyTemplate(MixedSplitTestCase):
         problem_block_course.weight = new_weight
         self.store.update_item(problem_block_course, self.user_id)
 
-        # Test that "Any previously existing children of `dest_usage` that haven't been replaced/updated by this copy_from_template operation will be deleted."
+        # Test that "Any previously existing children of `dest_usage`
+        # that haven't been replaced/updated by this copy_from_template operation will be deleted."
         extra_block = self.make_block("html", vertical_block_course)
 
         # Repeat the copy_from_template():
@@ -86,19 +94,26 @@ class TestSplitCopyTemplate(MixedSplitTestCase):
         display_name_expected = "CUSTOM Library Display Name"
         self.make_block("problem", source_library, display_name=display_name_expected)
         # Reload source_library since we need its branch and version to use copy_from_template:
-        source_library = self.store.get_library(source_library.location.library_key, remove_version=False, remove_branch=False)
+        source_library = self.store.get_library(
+            source_library.location.library_key, remove_version=False, remove_branch=False
+        )
         # And a course with a vertical:
         course = CourseFactory.create(modulestore=self.store)
         self.make_block("vertical", course)
 
-        problem_key_in_course = self.store.copy_from_template(source_library.children, dest_key=course.location, user_id=self.user_id)[0]
+        problem_key_in_course = self.store.copy_from_template(
+            source_library.children, dest_key=course.location, user_id=self.user_id
+        )[0]
 
-        # We do the following twice because different methods get used inside split modulestore on first vs. subsequent publish
+        # We do the following twice because different methods get used inside
+        # split modulestore on first vs. subsequent publish
         for __ in range(0, 2):
             # Publish:
             self.store.publish(problem_key_in_course, self.user_id)
             # Test that the defaults values are there.
-            problem_published = self.store.get_item(problem_key_in_course.for_branch(ModuleStoreEnum.BranchName.published))
+            problem_published = self.store.get_item(
+                problem_key_in_course.for_branch(ModuleStoreEnum.BranchName.published)
+            )
             self.assertEqual(problem_published.display_name, display_name_expected)
 
     def test_copy_from_template_auto_publish(self):
@@ -119,7 +134,9 @@ class TestSplitCopyTemplate(MixedSplitTestCase):
         html = self.make_block("html", source_course)
 
         # Reload source_course since we need its branch and version to use copy_from_template:
-        source_course = self.store.get_course(source_course.location.course_key, remove_version=False, remove_branch=False)
+        source_course = self.store.get_course(
+            source_course.location.course_key, remove_version=False, remove_branch=False
+        )
 
         # Inherit the vertical and the problem from the library into the course:
         source_keys = [block.location for block in [about, chapter, html]]
@@ -146,10 +163,13 @@ class TestSplitCopyTemplate(MixedSplitTestCase):
 
         # Check that the auto-publish blocks have been published:
         self.assertFalse(self.store.has_changes(new_blocks["about"]))
-        self.assertTrue(published_version_exists(new_blocks["chapter"]))  # We can't use has_changes because it includes descendants
+        # We can't use has_changes because it includes descendants
+        self.assertTrue(published_version_exists(new_blocks["chapter"]))
         self.assertTrue(published_version_exists(new_blocks["sequential"]))  # Ditto
         # Check that non-auto-publish blocks and blocks with non-auto-publish descendants show changes:
         self.assertTrue(self.store.has_changes(new_blocks["html"]))
         self.assertTrue(self.store.has_changes(new_blocks["problem"]))
-        self.assertTrue(self.store.has_changes(new_blocks["chapter"]))  # Will have changes since a child block has changes.
-        self.assertFalse(published_version_exists(new_blocks["vertical"]))  # Verify that our published_version_exists works
+        # Will have changes since a child block has changes.
+        self.assertTrue(self.store.has_changes(new_blocks["chapter"]))
+        # Verify that our published_version_exists works
+        self.assertFalse(published_version_exists(new_blocks["vertical"]))
diff --git a/common/lib/xmodule/xmodule/tests/test_library_content.py b/common/lib/xmodule/xmodule/tests/test_library_content.py
index 5f32dab130..0a60895f0a 100644
--- a/common/lib/xmodule/xmodule/tests/test_library_content.py
+++ b/common/lib/xmodule/xmodule/tests/test_library_content.py
@@ -195,7 +195,8 @@ class TestLibraryContentModule(LibraryContentTest):
         """
         # Set max_count to higher value than exists in library
         self.lc_block.max_count = 50
-        self.lc_block.refresh_children()  # In the normal studio editing process, editor_saved() calls refresh_children at this point
+        # In the normal studio editing process, editor_saved() calls refresh_children at this point
+        self.lc_block.refresh_children()
         result = self.lc_block.validate()
         self.assertFalse(result)  # Validation fails due to at least one warning/message
         self.assertTrue(result.summary)
@@ -269,7 +270,9 @@ class TestLibraryContentModule(LibraryContentTest):
         self.assertNotIn(LibraryContentDescriptor.display_name, non_editable_metadata_fields)
 
 
-@patch('xmodule.modulestore.split_mongo.caching_descriptor_system.CachingDescriptorSystem.render', VanillaRuntime.render)
+@patch(
+    'xmodule.modulestore.split_mongo.caching_descriptor_system.CachingDescriptorSystem.render', VanillaRuntime.render
+)
 @patch('xmodule.html_module.HtmlModule.author_view', dummy_render, create=True)
 @patch('xmodule.x_module.DescriptorSystem.applicable_aside_types', lambda self, block: [])
 class TestLibraryContentRender(LibraryContentTest):
diff --git a/common/lib/xmodule/xmodule/tests/test_library_root.py b/common/lib/xmodule/xmodule/tests/test_library_root.py
index 8774e7bb32..574bcf4152 100644
--- a/common/lib/xmodule/xmodule/tests/test_library_root.py
+++ b/common/lib/xmodule/xmodule/tests/test_library_root.py
@@ -14,7 +14,9 @@ from xmodule.modulestore.tests.utils import MixedSplitTestCase
 dummy_render = lambda block, _: Fragment(block.data)  # pylint: disable=invalid-name
 
 
-@patch('xmodule.modulestore.split_mongo.caching_descriptor_system.CachingDescriptorSystem.render', VanillaRuntime.render)
+@patch(
+    'xmodule.modulestore.split_mongo.caching_descriptor_system.CachingDescriptorSystem.render', VanillaRuntime.render
+)
 @patch('xmodule.html_module.HtmlDescriptor.author_view', dummy_render, create=True)
 @patch('xmodule.x_module.DescriptorSystem.applicable_aside_types', lambda self, block: [])
 class TestLibraryRoot(MixedSplitTestCase):
diff --git a/common/test/acceptance/fixtures/library.py b/common/test/acceptance/fixtures/library.py
index 5692c078db..a7a55d207d 100644
--- a/common/test/acceptance/fixtures/library.py
+++ b/common/test/acceptance/fixtures/library.py
@@ -82,9 +82,9 @@ class LibraryFixture(XBlockContainerFixture):
                 err_msg = response.json().get('ErrMsg')
             except ValueError:
                 err_msg = "Unknown Error"
-            raise FixtureError(
-                "Could not create library {}. Status was {}, error was: {}".format(self.library_info, response.status_code, err_msg)
-            )
+            raise FixtureError("Could not create library {}. Status was {}, error was: {}".format(
+                self.library_info, response.status_code, err_msg
+            ))
 
     def create_xblock(self, parent_loc, xblock_desc):
         # Disable publishing for library XBlocks:
diff --git a/common/test/acceptance/pages/studio/auto_auth.py b/common/test/acceptance/pages/studio/auto_auth.py
index 2e2cffd677..d3759b1136 100644
--- a/common/test/acceptance/pages/studio/auto_auth.py
+++ b/common/test/acceptance/pages/studio/auto_auth.py
@@ -15,7 +15,8 @@ class AutoAuthPage(PageObject):
     this url will create a user and log them in.
     """
 
-    def __init__(self, browser, username=None, email=None, password=None, staff=None, course_id=None, roles=None, no_login=None):
+    def __init__(self, browser, username=None, email=None, password=None,
+                 staff=None, course_id=None, roles=None, no_login=None):
         """
         Auto-auth is an end-point for HTTP GET requests.
         By default, it will create accounts with random user credentials,
diff --git a/common/test/acceptance/pages/studio/container.py b/common/test/acceptance/pages/studio/container.py
index 8f4ccb8590..88a05f9e02 100644
--- a/common/test/acceptance/pages/studio/container.py
+++ b/common/test/acceptance/pages/studio/container.py
@@ -365,6 +365,7 @@ class XBlockWrapper(PageObject):
         return self._validation_paragraph('error').present
 
     @property
+    # pylint: disable=invalid-name
     def has_validation_not_configured_warning(self):
         """ Is a validation "not configured" message shown? """
         return self._validation_paragraph('not-configured').present
@@ -380,6 +381,7 @@ class XBlockWrapper(PageObject):
         return self._validation_paragraph('error').text[0]
 
     @property
+    # pylint: disable=invalid-name
     def validation_not_configured_warning_text(self):
         """ Get the text of the validation "not configured" message. """
         return self._validation_paragraph('not-configured').text[0]
diff --git a/common/test/acceptance/pages/studio/index.py b/common/test/acceptance/pages/studio/index.py
index 2a69b43343..d6d6a25603 100644
--- a/common/test/acceptance/pages/studio/index.py
+++ b/common/test/acceptance/pages/studio/index.py
@@ -88,7 +88,8 @@ class DashboardPage(PageObject):
         """
         List all the libraries found on the page's list of libraries.
         """
-        self.q(css='#course-index-tabs .libraries-tab a').click()  # Workaround Selenium/Firefox bug: `.text` property is broken on invisible elements
+        # Workaround Selenium/Firefox bug: `.text` property is broken on invisible elements
+        self.q(css='#course-index-tabs .libraries-tab a').click()
         div2info = lambda element: {
             'name': element.find_element_by_css_selector('.course-title').text,
             'org': element.find_element_by_css_selector('.course-org .value').text,
diff --git a/common/test/acceptance/pages/studio/users.py b/common/test/acceptance/pages/studio/users.py
index c1a2427d56..5c0216f893 100644
--- a/common/test/acceptance/pages/studio/users.py
+++ b/common/test/acceptance/pages/studio/users.py
@@ -47,7 +47,9 @@ class UsersPage(PageObject):
         """
         Return a list of users listed on this page.
         """
-        return self.q(css='.user-list .user-item').map(lambda el: UserWrapper(self.browser, el.get_attribute('data-email'))).results
+        return self.q(css='.user-list .user-item').map(
+            lambda el: UserWrapper(self.browser, el.get_attribute('data-email'))
+        ).results
 
     @property
     def has_add_button(self):
diff --git a/common/test/acceptance/pages/studio/utils.py b/common/test/acceptance/pages/studio/utils.py
index dd8ec091a3..df86d5deca 100644
--- a/common/test/acceptance/pages/studio/utils.py
+++ b/common/test/acceptance/pages/studio/utils.py
@@ -118,7 +118,10 @@ def add_component(page, item_type, specific_type):
     if multiple_templates:
         sub_template_menu_div_selector = '.new-component-{}'.format(item_type)
         page.wait_for_element_visibility(sub_template_menu_div_selector, 'Wait for the templates sub-menu to appear')
-        page.wait_for_element_invisibility('.add-xblock-component .new-component', 'Wait for the add component menu to disappear')
+        page.wait_for_element_invisibility(
+            '.add-xblock-component .new-component',
+            'Wait for the add component menu to disappear'
+        )
 
         all_options = page.q(css='.new-component-{} ul.new-component-template li a span'.format(item_type))
         chosen_option = all_options.filter(lambda el: el.text == specific_type).first
diff --git a/common/test/acceptance/tests/studio/test_studio_general.py b/common/test/acceptance/tests/studio/test_studio_general.py
index c0b409b66b..adaa46227d 100644
--- a/common/test/acceptance/tests/studio/test_studio_general.py
+++ b/common/test/acceptance/tests/studio/test_studio_general.py
@@ -93,7 +93,7 @@ class CoursePagesTest(StudioCourseTest):
         /course/ is the base URL for all courses, but by itself, it should
         redirect to /home/.
         """
-        self.dashboard_page = DashboardPage(self.browser)
+        self.dashboard_page = DashboardPage(self.browser)  # pylint: disable=attribute-defined-outside-init
         self.dashboard_page.visit()
         self.assertEqual(self.browser.current_url.strip('/').rsplit('/')[-1], 'home')
 
diff --git a/common/test/acceptance/tests/studio/test_studio_library_container.py b/common/test/acceptance/tests/studio/test_studio_library_container.py
index 593243e628..175ee08539 100644
--- a/common/test/acceptance/tests/studio/test_studio_library_container.py
+++ b/common/test/acceptance/tests/studio/test_studio_library_container.py
@@ -26,10 +26,15 @@ class StudioLibraryContainerTest(StudioLibraryTest, UniqueCourseTest):
         """
         super(StudioLibraryContainerTest, self).setUp()
         # Also create a course:
-        self.course_fixture = CourseFixture(self.course_info['org'], self.course_info['number'], self.course_info['run'], self.course_info['display_name'])
+        self.course_fixture = CourseFixture(
+            self.course_info['org'], self.course_info['number'],
+            self.course_info['run'], self.course_info['display_name']
+        )
         self.populate_course_fixture(self.course_fixture)
         self.course_fixture.install()
-        self.outline = CourseOutlinePage(self.browser, self.course_info['org'], self.course_info['number'], self.course_info['run'])
+        self.outline = CourseOutlinePage(
+            self.browser, self.course_info['org'], self.course_info['number'], self.course_info['run']
+        )
 
         self.outline.visit()
         subsection = self.outline.section(SECTION_NAME).subsection(SUBSECTION_NAME)
@@ -156,7 +161,8 @@ class StudioLibraryContainerTest(StudioLibraryTest, UniqueCourseTest):
         library_block = self._get_library_xblock_wrapper(self.unit_page.xblocks[0])
 
         self.assertFalse(library_block.has_validation_warning)
-        #self.assertIn("3 matching components", library_block.author_content)  # Removed this assert until a summary message is added back to the author view (SOL-192)
+        # Removed this assert until a summary message is added back to the author view (SOL-192)
+        #self.assertIn("3 matching components", library_block.author_content)
 
         self.library_fixture.create_xblock(self.library_fixture.library_location, XBlockFixtureDesc("html", "Html4"))
 
@@ -171,7 +177,8 @@ class StudioLibraryContainerTest(StudioLibraryTest, UniqueCourseTest):
         library_block = self._get_library_xblock_wrapper(self.unit_page.xblocks[0])
 
         self.assertFalse(library_block.has_validation_message)
-        #self.assertIn("4 matching components", library_block.author_content)  # Removed this assert until a summary message is added back to the author view (SOL-192)
+        # Removed this assert until a summary message is added back to the author view (SOL-192)
+        #self.assertIn("4 matching components", library_block.author_content)
 
     def test_no_content_message(self):
         """