diff --git a/youtube_dl/FileDownloader.py b/youtube_dl/FileDownloader.py
index a861086c3c..d9a4ecd3a9 100644
--- a/youtube_dl/FileDownloader.py
+++ b/youtube_dl/FileDownloader.py
@@ -433,11 +433,8 @@ class FileDownloader(object):
             try:
                 srtfn = filename.rsplit('.', 1)[0] + u'.srt'
                 self.report_writesubtitles(srtfn)
-                srtfile = open(encodeFilename(srtfn), 'wb')
-                try:
-                    srtfile.write(info_dict['subtitles'].encode('utf-8'))
-                finally:
-                    srtfile.close()
+                with io.open(encodeFilename(srtfn), 'w', encoding='utf-8') as srtfile:
+                    srtfile.write(info_dict['subtitles'])
             except (OSError, IOError):
                 self.trouble(u'ERROR: Cannot write subtitles file ' + descfn)
                 return
diff --git a/youtube_dl/InfoExtractors.py b/youtube_dl/InfoExtractors.py
index aa4a6500b3..6201ccad7c 100755
--- a/youtube_dl/InfoExtractors.py
+++ b/youtube_dl/InfoExtractors.py
@@ -235,7 +235,7 @@ class YoutubeIE(InfoExtractor):
         elif 'en' in srt_lang_list:
             srt_lang = 'en'
         else:
-            srt_lang = srt_lang_list.keys()[0]
+            srt_lang = list(srt_lang_list.keys())[0]
         if not srt_lang in srt_lang_list:
             return (u'WARNING: no closed captions found in the specified language', None)
         request = compat_urllib_request.Request('http://www.youtube.com/api/timedtext?lang=%s&name=%s&v=%s' % (srt_lang, srt_lang_list[srt_lang], video_id))
@@ -445,7 +445,7 @@ class YoutubeIE(InfoExtractor):
         elif 'url_encoded_fmt_stream_map' in video_info and len(video_info['url_encoded_fmt_stream_map']) >= 1:
             url_data_strs = video_info['url_encoded_fmt_stream_map'][0].split(',')
             url_data = [compat_parse_qs(uds) for uds in url_data_strs]
-            url_data = filter(lambda ud: 'itag' in ud and 'url' in ud, url_data)
+            url_data = [ud for ud in url_data if 'itag' in ud and 'url' in ud]
             url_map = dict((ud['itag'][0], ud['url'][0] + '&signature=' + ud['sig'][0]) for ud in url_data)
 
             format_limit = self._downloader.params.get('format_limit', None)
@@ -2115,7 +2115,7 @@ class FacebookIE(InfoExtractor):
         video_description = video_info.get('description', 'No description available.')
 
         url_map = video_info['video_urls']
-        if len(url_map.keys()) > 0:
+        if len(list(url_map.keys())) > 0:
             # Decide which formats to download
             req_format = self._downloader.params.get('format', None)
             format_limit = self._downloader.params.get('format_limit', None)
@@ -2975,7 +2975,7 @@ class MixcloudIE(InfoExtractor):
                 if file_url is not None:
                     break # got it!
         else:
-            if req_format not in formats.keys():
+            if req_format not in list(formats.keys()):
                 self._downloader.trouble(u'ERROR: format is not available')
                 return
 
@@ -3274,7 +3274,7 @@ class YoukuIE(InfoExtractor):
             seed = config['data'][0]['seed']
 
             format = self._downloader.params.get('format', None)
-            supported_format = config['data'][0]['streamfileids'].keys()
+            supported_format = list(config['data'][0]['streamfileids'].keys())
 
             if format is None or format == 'best':
                 if 'hd2' in supported_format:
diff --git a/youtube_dl/__init__.py b/youtube_dl/__init__.py
index efa8b813f8..9b25ab3a2b 100644
--- a/youtube_dl/__init__.py
+++ b/youtube_dl/__init__.py
@@ -453,8 +453,8 @@ def _real_main():
     if opts.list_extractors:
         for ie in extractors:
             print(ie.IE_NAME + (' (CURRENTLY BROKEN)' if not ie._WORKING else ''))
-            matchedUrls = filter(lambda url: ie.suitable(url), all_urls)
-            all_urls = filter(lambda url: url not in matchedUrls, all_urls)
+            matchedUrls = [url for url in all_urls if ie.suitable(url)]
+            all_urls = [url for url in all_urls if url not in matchedUrls]
             for mu in matchedUrls:
                 print(u'  ' + mu)
         sys.exit(0)