diff --git a/scrapy/pipelines/files.py b/scrapy/pipelines/files.py
index 250f46ad8..a449793c9 100644
--- a/scrapy/pipelines/files.py
+++ b/scrapy/pipelines/files.py
@@ -7,9 +7,9 @@ See documentation in topics/media-pipeline.rst
 import hashlib
 import os
 import os.path
-import rfc822
 import time
 import logging
+from email.utils import parsedate_tz, mktime_tz
 from six.moves.urllib.parse import urlparse
 from collections import defaultdict
 import six
@@ -91,8 +91,8 @@ class S3FilesStore(object):
         def _onsuccess(boto_key):
             checksum = boto_key.etag.strip('"')
             last_modified = boto_key.last_modified
-            modified_tuple = rfc822.parsedate_tz(last_modified)
-            modified_stamp = int(rfc822.mktime_tz(modified_tuple))
+            modified_tuple = parsedate_tz(last_modified)
+            modified_stamp = int(mktime_tz(modified_tuple))
             return {'checksum': checksum, 'last_modified': modified_stamp}
 
         return self._get_boto_key(path).addCallback(_onsuccess)
diff --git a/scrapy/responsetypes.py b/scrapy/responsetypes.py
index 7c017feef..c212f5706 100644
--- a/scrapy/responsetypes.py
+++ b/scrapy/responsetypes.py
@@ -92,9 +92,9 @@ class ResponseTypes(object):
         chunk = body[:5000]
         if isbinarytext(chunk):
             return self.from_mimetype('application/octet-stream')
-        elif "<html>" in chunk.lower():
+        elif b"<html>" in chunk.lower():
             return self.from_mimetype('text/html')
-        elif "<?xml" in chunk.lower():
+        elif b"<?xml" in chunk.lower():
             return self.from_mimetype('text/xml')
         else:
             return self.from_mimetype('text')
diff --git a/scrapy/utils/defer.py b/scrapy/utils/defer.py
index 7a3f20476..8f3824abf 100644
--- a/scrapy/utils/defer.py
+++ b/scrapy/utils/defer.py
@@ -97,7 +97,7 @@ def iter_errback(iterable, errback, *a, **kw):
     iterating it.
     """
     it = iter(iterable)
-    while 1:
+    while True:
         try:
             yield next(it)
         except StopIteration:
diff --git a/scrapy/utils/misc.py b/scrapy/utils/misc.py
index c269b7f74..4215e41d2 100644
--- a/scrapy/utils/misc.py
+++ b/scrapy/utils/misc.py
@@ -106,7 +106,7 @@ def md5sum(file):
     '784406af91dd5a54fbb9c84c2236595a'
     """
     m = hashlib.md5()
-    while 1:
+    while True:
         d = file.read(8096)
         if not d:
             break
diff --git a/tests/py3-ignores.txt b/tests/py3-ignores.txt
index 4dfab4a9a..84bd01c0e 100644
--- a/tests/py3-ignores.txt
+++ b/tests/py3-ignores.txt
@@ -12,7 +12,6 @@ tests/test_crawler.py
 tests/test_downloader_handlers.py
 tests/test_downloadermiddleware_ajaxcrawlable.py
 tests/test_downloadermiddleware_cookies.py
-tests/test_downloadermiddleware_decompression.py
 tests/test_downloadermiddleware_defaultheaders.py
 tests/test_downloadermiddleware_downloadtimeout.py
 tests/test_downloadermiddleware_httpauth.py
@@ -28,10 +27,8 @@ tests/test_engine.py
 tests/test_http_cookies.py
 tests/test_logformatter.py
 tests/test_mail.py
-tests/test_middleware.py
 tests/test_pipeline_files.py
 tests/test_pipeline_images.py
-tests/test_pipeline_media.py
 tests/test_proxy_connect.py
 tests/test_responsetypes.py
 tests/test_selector_csstranslator.py
diff --git a/tests/test_downloadermiddleware_decompression.py b/tests/test_downloadermiddleware_decompression.py
index 9143611fc..77b35a8c3 100644
--- a/tests/test_downloadermiddleware_decompression.py
+++ b/tests/test_downloadermiddleware_decompression.py
@@ -39,7 +39,7 @@ class DecompressionMiddlewareTest(TestCase):
         assert_samelines(self, new.body, rsp.body)
 
     def test_empty_response(self):
-        rsp = Response(url='http://test.com', body='')
+        rsp = Response(url='http://test.com', body=b'')
         new = self.mw.process_response(None, rsp, self.spider)
         assert new is rsp
         assert not rsp.body
diff --git a/tests/test_middleware.py b/tests/test_middleware.py
index 48131462c..b6d885330 100644
--- a/tests/test_middleware.py
+++ b/tests/test_middleware.py
@@ -3,6 +3,7 @@ from twisted.trial import unittest
 from scrapy.settings import Settings
 from scrapy.exceptions import NotConfigured
 from scrapy.middleware import MiddlewareManager
+import six
 
 class M1(object):
 
@@ -65,12 +66,20 @@ class MiddlewareManagerTest(unittest.TestCase):
 
     def test_methods(self):
         mwman = TestMiddlewareManager(M1(), M2(), M3())
-        self.assertEqual([x.im_class for x in mwman.methods['open_spider']],
-            [M1, M2])
-        self.assertEqual([x.im_class for x in mwman.methods['close_spider']],
-            [M2, M1])
-        self.assertEqual([x.im_class for x in mwman.methods['process']],
-            [M1, M3])
+        if six.PY2:
+            self.assertEqual([x.im_class for x in mwman.methods['open_spider']],
+                [M1, M2])
+            self.assertEqual([x.im_class for x in mwman.methods['close_spider']],
+                [M2, M1])
+            self.assertEqual([x.im_class for x in mwman.methods['process']],
+                [M1, M3])
+        else:
+            self.assertEqual([x.__self__.__class__ for x in mwman.methods['open_spider']],
+                [M1, M2])
+            self.assertEqual([x.__self__.__class__ for x in mwman.methods['close_spider']],
+                [M2, M1])
+            self.assertEqual([x.__self__.__class__ for x in mwman.methods['process']],
+                [M1, M3])
 
     def test_enabled(self):
         m1, m2, m3 = M1(), M2(), M3()
diff --git a/tests/test_pipeline_files.py b/tests/test_pipeline_files.py
index b12f41174..ac0438eba 100644
--- a/tests/test_pipeline_files.py
+++ b/tests/test_pipeline_files.py
@@ -192,7 +192,7 @@ def _create_item_with_files(*files):
 def _prepare_request_object(item_url):
     return Request(
         item_url,
-        meta={'response': Response(item_url, status=200, body='data')})
+        meta={'response': Response(item_url, status=200, body=b'data')})
 
 
 if __name__ == "__main__":
diff --git a/tests/test_pipeline_media.py b/tests/test_pipeline_media.py
index fd8b28ce1..f30b4fea3 100644
--- a/tests/test_pipeline_media.py
+++ b/tests/test_pipeline_media.py
@@ -44,7 +44,7 @@ class BaseMediaPipelineTestCase(unittest.TestCase):
 
     def test_default_media_downloaded(self):
         request = Request('http://url')
-        response = Response('http://url', body='')
+        response = Response('http://url', body=b'')
         assert self.pipe.media_downloaded(response, request, self.info) is response
 
     def test_default_media_failed(self):
diff --git a/tests/test_responsetypes.py b/tests/test_responsetypes.py
index b4083403a..1d78d0976 100644
--- a/tests/test_responsetypes.py
+++ b/tests/test_responsetypes.py
@@ -51,7 +51,7 @@ class ResponseTypesTest(unittest.TestCase):
         for source, cls in mappings:
             retcls = responsetypes.from_body(source)
             assert retcls is cls, "%s ==> %s != %s" % (source, retcls, cls)
-        
+
     def test_from_headers(self):
         mappings = [
             ({'Content-Type': ['text/html; charset=utf-8']}, HtmlResponse),
