diff --git a/pytest.ini b/pytest.ini
index 998633d541cab44c0f0574cc161fab2ebb5b0d5d..1570a3a75dd70248396470ec0458e9e3bea1e951 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -50,26 +50,26 @@ flake8-ignore =
     scrapy/core/engine.py E501 E128
     scrapy/core/scheduler.py E501
     scrapy/core/scraper.py E501 E128
-    scrapy/core/spidermw.py E501 E126
+    scrapy/core/spidermw.py E501
     scrapy/core/downloader/__init__.py E501
-    scrapy/core/downloader/contextfactory.py E501 E128 E126
+    scrapy/core/downloader/contextfactory.py E501 E128
     scrapy/core/downloader/middleware.py E501
     scrapy/core/downloader/tls.py E501
-    scrapy/core/downloader/webclient.py E501 E128 E126
+    scrapy/core/downloader/webclient.py E501 E128
     scrapy/core/downloader/handlers/__init__.py E501
     scrapy/core/downloader/handlers/ftp.py E501 E128
     scrapy/core/downloader/handlers/http10.py E501
     scrapy/core/downloader/handlers/http11.py E501
-    scrapy/core/downloader/handlers/s3.py E501 E128 E126
+    scrapy/core/downloader/handlers/s3.py E501 E128
     # scrapy/downloadermiddlewares
     scrapy/downloadermiddlewares/ajaxcrawl.py E501
     scrapy/downloadermiddlewares/decompression.py E501
     scrapy/downloadermiddlewares/defaultheaders.py E501
-    scrapy/downloadermiddlewares/httpcache.py E501 E126
+    scrapy/downloadermiddlewares/httpcache.py E501
     scrapy/downloadermiddlewares/httpcompression.py E501 E128
     scrapy/downloadermiddlewares/httpproxy.py E501
     scrapy/downloadermiddlewares/redirect.py E501
-    scrapy/downloadermiddlewares/retry.py E501 E126
+    scrapy/downloadermiddlewares/retry.py E501
     scrapy/downloadermiddlewares/robotstxt.py E501
     scrapy/downloadermiddlewares/stats.py E501
     # scrapy/extensions
@@ -164,12 +164,12 @@ flake8-ignore =
     scrapy/robotstxt.py E501
     scrapy/shell.py E501
     scrapy/signalmanager.py E501
-    scrapy/spiderloader.py F841 E501 E126
+    scrapy/spiderloader.py F841 E501
     scrapy/squeues.py E128
     scrapy/statscollectors.py E501
     # tests
     tests/__init__.py E402 E501
-    tests/mockserver.py E501 E126
+    tests/mockserver.py E501
     tests/pipelines.py F841
     tests/spiders.py E501
     tests/test_closespider.py E501
@@ -181,18 +181,18 @@ flake8-ignore =
     tests/test_crawl.py E501 E741
     tests/test_crawler.py F841 E501
     tests/test_dependencies.py F841 E501
-    tests/test_downloader_handlers.py E128 E501 E126
+    tests/test_downloader_handlers.py E128 E501
     tests/test_downloadermiddleware.py E501
     tests/test_downloadermiddleware_ajaxcrawlable.py E501
-    tests/test_downloadermiddleware_cookies.py E741 E501 E128 E126
+    tests/test_downloadermiddleware_cookies.py E741 E501 E128
     tests/test_downloadermiddleware_defaultheaders.py E501
     tests/test_downloadermiddleware_downloadtimeout.py E501
     tests/test_downloadermiddleware_httpcache.py E501
-    tests/test_downloadermiddleware_httpcompression.py E501 E126
+    tests/test_downloadermiddleware_httpcompression.py E501
     tests/test_downloadermiddleware_decompression.py E501
     tests/test_downloadermiddleware_httpproxy.py E501 E128
     tests/test_downloadermiddleware_redirect.py E501 E128
-    tests/test_downloadermiddleware_retry.py E501 E128 E126
+    tests/test_downloadermiddleware_retry.py E501 E128
     tests/test_downloadermiddleware_robotstxt.py E501
     tests/test_downloadermiddleware_stats.py E501
     tests/test_dupefilters.py E501 E741 E128
@@ -202,7 +202,7 @@ flake8-ignore =
     tests/test_feedexport.py E501 F841
     tests/test_http_cookies.py E501
     tests/test_http_headers.py E501
-    tests/test_http_request.py E402 E501 E128 E128 E126
+    tests/test_http_request.py E402 E501 E128 E128
     tests/test_http_response.py E501 E128
     tests/test_item.py E128 F841
     tests/test_link.py E501
@@ -211,7 +211,7 @@ flake8-ignore =
     tests/test_logformatter.py E128 E501
     tests/test_mail.py E128 E501
     tests/test_middleware.py E501 E128
-    tests/test_pipeline_crawl.py E501 E128 E126
+    tests/test_pipeline_crawl.py E501 E128
     tests/test_pipeline_files.py E501
     tests/test_pipeline_images.py F841 E501
     tests/test_pipeline_media.py E501 E741 E128
@@ -219,7 +219,7 @@ flake8-ignore =
     tests/test_request_cb_kwargs.py E501
     tests/test_responsetypes.py E501
     tests/test_robotstxt_interface.py E501 E501
-    tests/test_scheduler.py E501 E126
+    tests/test_scheduler.py E501
     tests/test_selector.py E501
     tests/test_spider.py E501
     tests/test_spidermiddleware.py E501
@@ -243,8 +243,8 @@ flake8-ignore =
     tests/test_utils_response.py E501
     tests/test_utils_signal.py E741 F841
     tests/test_utils_sitemap.py E128 E501
-    tests/test_utils_url.py E501 E501 E126
-    tests/test_webclient.py E501 E128 E402 E126
+    tests/test_utils_url.py E501 E501
+    tests/test_webclient.py E501 E128 E402
     tests/test_cmdline/__init__.py E501
     tests/test_settings/__init__.py E501 E128
     tests/test_spiderloader/__init__.py E128 E501
diff --git a/scrapy/core/downloader/contextfactory.py b/scrapy/core/downloader/contextfactory.py
index 6e023ebcc99bb145d86f7b6fbebf247bac82f664..ab73e12c844c355b23ce38a8ba85a282672bcb57 100644
--- a/scrapy/core/downloader/contextfactory.py
+++ b/scrapy/core/downloader/contextfactory.py
@@ -86,8 +86,8 @@ class BrowserLikeContextFactory(ScrapyClientContextFactory):
         #
         # This means that a website like https://www.cacert.org will be rejected
         # by default, since CAcert.org CA certificate is seldom shipped.
-        return optionsForClientTLS(hostname.decode("ascii"),
-                                   trustRoot=platformTrust(),
-                                   extraCertificateOptions={
-                                        'method': self._ssl_method,
-                                   })
+        return optionsForClientTLS(
+            hostname=hostname.decode("ascii"),
+            trustRoot=platformTrust(),
+            extraCertificateOptions={'method': self._ssl_method},
+        )
diff --git a/scrapy/core/downloader/handlers/s3.py b/scrapy/core/downloader/handlers/s3.py
index 40a1fa48ecd2970a6244eb5ce9385a5dd89fa6b8..8f63ad9742749eaeb5b5f1f0ef120ff05cf0ab76 100644
--- a/scrapy/core/downloader/handlers/s3.py
+++ b/scrapy/core/downloader/handlers/s3.py
@@ -100,11 +100,12 @@ class S3DownloadHandler:
                 url=url, headers=awsrequest.headers.items())
         else:
             signed_headers = self.conn.make_request(
-                    method=request.method,
-                    bucket=bucket,
-                    key=unquote(p.path),
-                    query_args=unquote(p.query),
-                    headers=request.headers,
-                    data=request.body)
+                method=request.method,
+                bucket=bucket,
+                key=unquote(p.path),
+                query_args=unquote(p.query),
+                headers=request.headers,
+                data=request.body,
+            )
             request = request.replace(url=url, headers=signed_headers)
         return self._download_http(request, spider)
diff --git a/scrapy/core/downloader/webclient.py b/scrapy/core/downloader/webclient.py
index a90a77b2b176e15a9b5a4904f169caefbbdafe1c..355045d748077b2f4e1d0187f0ab71f254e85428 100644
--- a/scrapy/core/downloader/webclient.py
+++ b/scrapy/core/downloader/webclient.py
@@ -88,8 +88,8 @@ class ScrapyHTTPPageGetter(HTTPClient):
             self.transport.stopProducing()
 
         self.factory.noPage(
-                defer.TimeoutError("Getting %s took longer than %s seconds." %
-                                   (self.factory.url, self.factory.timeout)))
+            defer.TimeoutError("Getting %s took longer than %s seconds."
+                               % (self.factory.url, self.factory.timeout)))
 
 
 class ScrapyHTTPClientFactory(HTTPClientFactory):
diff --git a/scrapy/downloadermiddlewares/retry.py b/scrapy/downloadermiddlewares/retry.py
index bbf5fca051269dd6c3a1714fb314057e6acdec56..6d11af5b22f548d7231ace69d3cd56d8b23a4d3d 100644
--- a/scrapy/downloadermiddlewares/retry.py
+++ b/scrapy/downloadermiddlewares/retry.py
@@ -12,9 +12,15 @@ once the spider has finished crawling all regular (non failed) pages.
 import logging
 
 from twisted.internet import defer
-from twisted.internet.error import TimeoutError, DNSLookupError, \
-        ConnectionRefusedError, ConnectionDone, ConnectError, \
-        ConnectionLost, TCPTimedOutError
+from twisted.internet.error import (
+    ConnectError,
+    ConnectionDone,
+    ConnectionLost,
+    ConnectionRefusedError,
+    DNSLookupError,
+    TCPTimedOutError,
+    TimeoutError,
+)
 from twisted.web.client import ResponseFailed
 
 from scrapy.exceptions import NotConfigured
diff --git a/scrapy/spiderloader.py b/scrapy/spiderloader.py
index 3be5aaec57c20edc097ea75cb79601b8d9cfe6dd..8dc89c2e911b4a57fbba2ce96baee5950134c1a8 100644
--- a/scrapy/spiderloader.py
+++ b/scrapy/spiderloader.py
@@ -24,15 +24,17 @@ class SpiderLoader:
         self._load_all_spiders()
 
     def _check_name_duplicates(self):
-        dupes = ["\n".join("  {cls} named {name!r} (in {module})".format(
-                                module=mod, cls=cls, name=name)
-                           for (mod, cls) in locations)
-                 for name, locations in self._found.items()
-                 if len(locations) > 1]
+        dupes = []
+        for name, locations in self._found.items():
+            dupes.extend([
+                "  {cls} named {name!r} (in {module})".format(module=mod, cls=cls, name=name)
+                for mod, cls in locations
+            ])
+
         if dupes:
+            dupes_string = "\n\n".join(dupes)
             msg = ("There are several spiders with the same name:\n\n"
-                   "{}\n\n  This can cause unexpected behavior.".format(
-                        "\n\n".join(dupes)))
+                   "{}\n\n  This can cause unexpected behavior.".format(dupes_string))
             warnings.warn(msg, UserWarning)
 
     def _load_spiders(self, module):
@@ -45,11 +47,12 @@ class SpiderLoader:
             try:
                 for module in walk_modules(name):
                     self._load_spiders(module)
-            except ImportError as e:
+            except ImportError:
                 if self.warn_only:
-                    msg = ("\n{tb}Could not load spiders from module '{modname}'. "
-                           "See above traceback for details.".format(
-                                modname=name, tb=traceback.format_exc()))
+                    msg = (
+                        "\n{tb}Could not load spiders from module '{modname}'. "
+                        "See above traceback for details.".format(modname=name, tb=traceback.format_exc())
+                    )
                     warnings.warn(msg, RuntimeWarning)
                 else:
                     raise
diff --git a/tests/test_downloadermiddleware_cookies.py b/tests/test_downloadermiddleware_cookies.py
index b686a14d672d54c7758ad8db54182dcc473aee05..f86c50f50a13826159aa813e5c819fb55f86f3c3 100644
--- a/tests/test_downloadermiddleware_cookies.py
+++ b/tests/test_downloadermiddleware_cookies.py
@@ -139,10 +139,12 @@ class CookiesMiddlewareTest(TestCase):
 
     def test_complex_cookies(self):
         # merge some cookies into jar
-        cookies = [{'name': 'C1', 'value': 'value1', 'path': '/foo', 'domain': 'scrapytest.org'},
-                {'name': 'C2', 'value': 'value2', 'path': '/bar', 'domain': 'scrapytest.org'},
-                {'name': 'C3', 'value': 'value3', 'path': '/foo', 'domain': 'scrapytest.org'},
-                {'name': 'C4', 'value': 'value4', 'path': '/foo', 'domain': 'scrapy.org'}]
+        cookies = [
+            {'name': 'C1', 'value': 'value1', 'path': '/foo', 'domain': 'scrapytest.org'},
+            {'name': 'C2', 'value': 'value2', 'path': '/bar', 'domain': 'scrapytest.org'},
+            {'name': 'C3', 'value': 'value3', 'path': '/foo', 'domain': 'scrapytest.org'},
+            {'name': 'C4', 'value': 'value4', 'path': '/foo', 'domain': 'scrapy.org'},
+        ]
 
         req = Request('http://scrapytest.org/', cookies=cookies)
         self.mw.process_request(req, self.spider)
diff --git a/tests/test_downloadermiddleware_retry.py b/tests/test_downloadermiddleware_retry.py
index 9c989977e8dd7160968026b92b86fe10f56e4154..e118750e39dca38bddb060beb6c6dc525709bb39 100644
--- a/tests/test_downloadermiddleware_retry.py
+++ b/tests/test_downloadermiddleware_retry.py
@@ -1,8 +1,14 @@
 import unittest
 from twisted.internet import defer
-from twisted.internet.error import TimeoutError, DNSLookupError, \
-        ConnectionRefusedError, ConnectionDone, ConnectError, \
-        ConnectionLost, TCPTimedOutError
+from twisted.internet.error import (
+    ConnectError,
+    ConnectionDone,
+    ConnectionLost,
+    ConnectionRefusedError,
+    DNSLookupError,
+    TCPTimedOutError,
+    TimeoutError,
+)
 from twisted.web.client import ResponseFailed
 
 from scrapy.downloadermiddlewares.retry import RetryMiddleware
diff --git a/tests/test_http_request.py b/tests/test_http_request.py
index 3b6d119a9880f2e30fa388b6be63f41018dd6253..77da15ce683c973356403eb0590fbe203cf92045 100644
--- a/tests/test_http_request.py
+++ b/tests/test_http_request.py
@@ -502,11 +502,13 @@ class FormRequestTest(RequestTest):
 
     def test_from_response_duplicate_form_key(self):
         response = _buildresponse(
-                '<form></form>',
-                url='http://www.example.com')
-        req = self.request_class.from_response(response,
-                method='GET',
-                formdata=(('foo', 'bar'), ('foo', 'baz')))
+            '<form></form>',
+            url='http://www.example.com')
+        req = self.request_class.from_response(
+            response=response,
+            method='GET',
+            formdata=(('foo', 'bar'), ('foo', 'baz')),
+        )
         self.assertEqual(urlparse(req.url).hostname, 'www.example.com')
         self.assertEqual(urlparse(req.url).query, 'foo=bar&foo=baz')
 
@@ -530,9 +532,11 @@ class FormRequestTest(RequestTest):
             <input type="hidden" name="test" value="val2">
             <input type="hidden" name="test2" value="xxx">
             </form>""")
-        req = self.request_class.from_response(response,
-                formdata={'one': ['two', 'three'], 'six': 'seven'},
-                headers={"Accept-Encoding": "gzip,deflate"})
+        req = self.request_class.from_response(
+            response=response,
+            formdata={'one': ['two', 'three'], 'six': 'seven'},
+            headers={"Accept-Encoding": "gzip,deflate"},
+        )
         self.assertEqual(req.method, 'POST')
         self.assertEqual(req.headers['Content-type'], b'application/x-www-form-urlencoded')
         self.assertEqual(req.headers['Accept-Encoding'], b'gzip,deflate')
@@ -580,9 +584,9 @@ class FormRequestTest(RequestTest):
 
     def test_from_response_override_method(self):
         response = _buildresponse(
-                '''<html><body>
-                <form action="/app"></form>
-                </body></html>''')
+            '''<html><body>
+            <form action="/app"></form>
+            </body></html>''')
         request = FormRequest.from_response(response)
         self.assertEqual(request.method, 'GET')
         request = FormRequest.from_response(response, method='POST')
@@ -590,9 +594,9 @@ class FormRequestTest(RequestTest):
 
     def test_from_response_override_url(self):
         response = _buildresponse(
-                '''<html><body>
-                <form action="/app"></form>
-                </body></html>''')
+            '''<html><body>
+            <form action="/app"></form>
+            </body></html>''')
         request = FormRequest.from_response(response)
         self.assertEqual(request.url, 'http://example.com/app')
         request = FormRequest.from_response(response, url='http://foo.bar/absolute')
diff --git a/tests/test_pipeline_crawl.py b/tests/test_pipeline_crawl.py
index 962c3314402976ff6851371968e2a1743ce80168..24c5164736f54d7c4cd1e0c2799b156eb43055e9 100644
--- a/tests/test_pipeline_crawl.py
+++ b/tests/test_pipeline_crawl.py
@@ -44,9 +44,7 @@ class RedirectedMediaDownloadSpider(MediaDownloadSpider):
     name = 'redirectedmedia'
 
     def _process_url(self, url):
-        return add_or_replace_parameter(
-                    self.mockserver.url('/redirect-to'),
-                    'goto', url)
+        return add_or_replace_parameter(self.mockserver.url('/redirect-to'), 'goto', url)
 
 
 class FileDownloadCrawlTestCase(TestCase):
diff --git a/tests/test_webclient.py b/tests/test_webclient.py
index b657c7ab6dd54b53059cda935ee28f49023c5818..307fadb5ce36c18babd1feae2b44ac01e581ef39 100644
--- a/tests/test_webclient.py
+++ b/tests/test_webclient.py
@@ -18,6 +18,14 @@ except ImportError:
 from twisted.python.filepath import FilePath
 from twisted.protocols.policies import WrappingFactory
 from twisted.internet.defer import inlineCallbacks
+from twisted.web.test.test_webclient import (
+    ForeverTakingResource,
+    ErrorResource,
+    NoLengthResource,
+    HostHeaderResource,
+    PayloadResource,
+    BrokenDownloadResource,
+)
 
 from scrapy.core.downloader import webclient as client
 from scrapy.core.downloader.contextfactory import ScrapyClientContextFactory
@@ -202,11 +210,6 @@ class ScrapyHTTPPageGetterTests(unittest.TestCase):
             Headers({'Hello': ['World'], 'Foo': ['Bar']}))
 
 
-from twisted.web.test.test_webclient import ForeverTakingResource, \
-        ErrorResource, NoLengthResource, HostHeaderResource, \
-        PayloadResource, BrokenDownloadResource
-
-
 class EncodingResource(resource.Resource):
     out_encoding = 'cp1251'