Repository: ytdl-org/youtube-dl

Issue:
C-span 
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## Checklist

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Carefully read and work through this check list in order to prevent the most common mistakes and misuse of youtube-dl:
- First of, make sure you are using the latest version of youtube-dl. Run `youtube-dl --version` and ensure your version is 2020.06.16.1. If it's not, see https://yt-dl.org/update on how to update. Issues with outdated version will be REJECTED.
- Make sure that all provided video/audio/playlist URLs (if any) are alive and playable in a browser.
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- [x] I'm reporting a broken site support
- [ ] I've verified that I'm running youtube-dl version **2020.06.16.1**
- [ ] I've checked that all provided URLs are alive and playable in a browser
- [ ] I've checked that all URLs and arguments with special characters are properly quoted or escaped
- [ ] I've searched the bugtracker for similar issues including closed ones


## Verbose log

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Provide the complete verbose output of youtube-dl that clearly demonstrates the problem.
Add the `-v` flag to your command line you run youtube-dl with (`youtube-dl -v <your command line>`), copy the WHOLE output and insert it below. It should look similar to this:
 [debug] System config: []
 [debug] User config: []
 [debug] Command-line args: [u'-v', u'http://www.youtube.com/watch?v=BaW_jenozKcj']
 [debug] Encodings: locale cp1251, fs mbcs, out cp866, pref cp1251
 [debug] youtube-dl version 2020.06.16.1
 [debug] Python version 2.7.11 - Windows-2003Server-5.2.3790-SP2
 [debug] exe versions: ffmpeg N-75573-g1d0487f, ffprobe N-75573-g1d0487f, rtmpdump 2.4
 [debug] Proxy map: {}
 <more lines>
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PASTE VERBOSE LOG HERE
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## Description

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WRITE DESCRIPTION HERE
Youtube-dl won't download videos from C-span, it gives me:
C:\Users\user\Downloads\youtube-dl>youtube-dl https://www.c-span.org/video/?175131-1/iraq-war-terrorism
[CSpan] 175131: Downloading webpage
[CSpan] 115590: Downloading JSON metadata
[CSpan] 115590: Downloading XML
[CSpan] 115590: Downloading m3u8 information
[hlsnative] Downloading m3u8 manifest
[hlsnative] Total fragments: 639
[download] Destination: Iraq and the War on Terrorism-115590.mp4
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 1 (attempt 1 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 1 (attempt 2 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 1 (attempt 3 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 1 (attempt 4 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 1 (attempt 5 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 1 (attempt 6 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 1 (attempt 7 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 1 (attempt 8 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 1 (attempt 9 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 1 (attempt 10 of 10)...
[download] Skipping fragment 1...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 2 (attempt 1 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 2 (attempt 2 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 2 (attempt 3 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 2 (attempt 4 of 10)...
[download] Got server HTTP error: HTTP Error 403: Forbidden. Retrying fragment 2 (attempt 5 of 10)...
and continues without downloading anything 



Discussion:
Use --referer as a workaround for the time being.

`youtube-dl https://www.c-span.org/video/?175131-1/iraq-war-terrorism -f hls-369 --referer https://www.c-span.org/video/?175131-1/iraq-war-terrorism`

Resolving patch:
diff --git a/youtube_dl/extractor/cspan.py b/youtube_dl/extractor/cspan.py
--- a/youtube_dl/extractor/cspan.py
+++ b/youtube_dl/extractor/cspan.py
@@ -165,6 +165,8 @@ def get_text_attr(d, attr):
                 formats = self._extract_m3u8_formats(
                     path, video_id, 'mp4', entry_protocol='m3u8_native',
                     m3u8_id='hls') if determine_ext(path) == 'm3u8' else [{'url': path, }]
+            for f in formats:
+                f.setdefault('http_headers', {})['Referer'] = url
             self._sort_formats(formats)
             entries.append({
                 'id': '%s_%d' % (video_id, partnum + 1),


Test patch: