diff --git a/youtube_dl/downloader/f4m.py b/youtube_dl/downloader/f4m.py
index ef3e0d5f44..f9f6f3e734 100644
--- a/youtube_dl/downloader/f4m.py
+++ b/youtube_dl/downloader/f4m.py
@@ -203,7 +203,7 @@ def write_flv_header(stream, metadata):
     stream.write(b'\x00\x00\x00\x00\x00\x00\x00')
     stream.write(metadata)
     # Magic numbers extracted from the output files produced by AdobeHDS.php
-    #(https://github.com/K-S-V/Scripts)
+    # (https://github.com/K-S-V/Scripts)
     stream.write(b'\x00\x00\x01\x73')
 
 
diff --git a/youtube_dl/downloader/rtmp.py b/youtube_dl/downloader/rtmp.py
index 5759126751..5346cb9a0a 100644
--- a/youtube_dl/downloader/rtmp.py
+++ b/youtube_dl/downloader/rtmp.py
@@ -185,7 +185,7 @@ class RtmpFD(FileDownloader):
             cursize = os.path.getsize(encodeFilename(tmpfilename))
             if prevsize == cursize and retval == RD_FAILED:
                 break
-             # Some rtmp streams seem abort after ~ 99.8%. Don't complain for those
+            # Some rtmp streams seem abort after ~ 99.8%. Don't complain for those
             if prevsize == cursize and retval == RD_INCOMPLETE and cursize > 1024:
                 self.to_screen('[rtmpdump] Could not download the whole video. This can happen for some advertisements.')
                 retval = RD_SUCCESS
diff --git a/youtube_dl/extractor/crunchyroll.py b/youtube_dl/extractor/crunchyroll.py
index 8f1ea02e74..2c7756eb6a 100644
--- a/youtube_dl/extractor/crunchyroll.py
+++ b/youtube_dl/extractor/crunchyroll.py
@@ -32,7 +32,6 @@ class CrunchyrollIE(SubtitlesInfoExtractor):
     _VALID_URL = r'https?://(?:(?P<prefix>www|m)\.)?(?P<url>crunchyroll\.com/(?:[^/]*/[^/?&]*?|media/\?id=)(?P<video_id>[0-9]+))(?:[/?&]|$)'
     _TEST = {
         'url': 'http://www.crunchyroll.com/wanna-be-the-strongest-in-the-world/episode-1-an-idol-wrestler-is-born-645513',
-        #'md5': 'b1639fd6ddfaa43788c85f6d1dddd412',
         'info_dict': {
             'id': '645513',
             'ext': 'flv',
diff --git a/youtube_dl/extractor/cspan.py b/youtube_dl/extractor/cspan.py
index 5411066846..955119d40b 100644
--- a/youtube_dl/extractor/cspan.py
+++ b/youtube_dl/extractor/cspan.py
@@ -27,7 +27,6 @@ class CSpanIE(InfoExtractor):
         'url': 'http://www.c-span.org/video/?c4486943/cspan-international-health-care-models',
         # For whatever reason, the served video alternates between
         # two different ones
-        #'md5': 'dbb0f047376d457f2ab8b3929cbb2d0c',
         'info_dict': {
             'id': '340723',
             'ext': 'mp4',
diff --git a/youtube_dl/extractor/tenplay.py b/youtube_dl/extractor/tenplay.py
index 81ba169fbe..466155ef80 100644
--- a/youtube_dl/extractor/tenplay.py
+++ b/youtube_dl/extractor/tenplay.py
@@ -8,7 +8,6 @@ class TenPlayIE(InfoExtractor):
     _VALID_URL = r'https?://(?:www\.)?ten(play)?\.com\.au/.+'
     _TEST = {
         'url': 'http://tenplay.com.au/ten-insider/extra/season-2013/tenplay-tv-your-way',
-        #'md5': 'd68703d9f73dc8fccf3320ab34202590',
         'info_dict': {
             'id': '2695695426001',
             'ext': 'flv',
diff --git a/youtube_dl/extractor/youtube.py b/youtube_dl/extractor/youtube.py
index 100ecbc0a1..550e18733e 100644
--- a/youtube_dl/extractor/youtube.py
+++ b/youtube_dl/extractor/youtube.py
@@ -527,8 +527,8 @@ class YoutubeIE(YoutubeBaseInfoExtractor, SubtitlesInfoExtractor):
                 return 's[%s%s%s]' % (starts, ends, steps)
 
             step = None
-            start = '(Never used)'  # Quelch pyflakes warnings - start will be
-                                    # set as soon as step is set
+            # Quelch pyflakes warnings - start will be set when step is set
+            start = '(Never used)'
             for i, prev in zip(idxs[1:], idxs[:-1]):
                 if step is not None:
                     if i - prev == step:
diff --git a/youtube_dl/utils.py b/youtube_dl/utils.py
index f9938616d6..43b7c94ba4 100644
--- a/youtube_dl/utils.py
+++ b/youtube_dl/utils.py
@@ -363,7 +363,7 @@ def encodeArgument(s):
     if not isinstance(s, compat_str):
         # Legacy code that uses byte strings
         # Uncomment the following line after fixing all post processors
-        #assert False, 'Internal error: %r should be of type %r, is %r' % (s, compat_str, type(s))
+        # assert False, 'Internal error: %r should be of type %r, is %r' % (s, compat_str, type(s))
         s = s.decode('ascii')
     return encodeFilename(s, True)