[extractor] Document netrc machines

Closes #3169

devscripts/make_supportedsites.py

@@ -5,38 +5,19 @@ import sys
 
 sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 
-import yt_dlp
+from yt_dlp.extractor import list_extractors
 
 
 def main():
     parser = optparse.OptionParser(usage='%prog OUTFILE.md')
-    options, args = parser.parse_args()
+    _, args = parser.parse_args()
     if len(args) != 1:
         parser.error('Expected an output filename')
 
-    outfile, = args
+    out = '\n'.join(ie.description() for ie in list_extractors(None) if ie.IE_DESC is not False)
 
-    def gen_ies_md(ies):
-        for ie in ies:
-            ie_md = f'**{ie.IE_NAME}**'
-            if ie.IE_DESC is False:
-                continue
-            if ie.IE_DESC is not None:
-                ie_md += f': {ie.IE_DESC}'
-            search_key = getattr(ie, 'SEARCH_KEY', None)
-            if search_key is not None:
-                ie_md += f'; "{ie.SEARCH_KEY}:" prefix'
-            if not ie.working():
-                ie_md += ' (Currently broken)'
-            yield ie_md
-
-    ies = sorted(yt_dlp.gen_extractors(), key=lambda i: i.IE_NAME.lower())
-    out = '# Supported sites\n' + ''.join(
-        ' - ' + md + '\n'
-        for md in gen_ies_md(ies))
-
-    with open(outfile, 'w', encoding='utf-8') as outf:
-        outf.write(out)
+    with open(args[0], 'w', encoding='utf-8') as outf:
+        outf.write(f'# Supported sites\n{out}\n')
 
 
 if __name__ == '__main__':