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Co-authored-by: bashonly <88596187+bashonly@users.noreply.github.com>

yt_dlp/extractor/common.py

@@ -2644,8 +2644,7 @@ class InfoExtractor:
                 'timescale': 1,
             })
             for adaptation_set in period.findall(_add_ns('AdaptationSet')):
-                role_node = adaptation_set.find(_add_ns('Role'))
+                role = try_call(lambda: adaptation_set.find(_add_ns('Role')).attrib['value'])
-
                 adaption_set_ms_info = extract_multisegment_info(adaptation_set, period_ms_info)
                 for representation in adaptation_set.findall(_add_ns('Representation')):
                     representation_attrib = adaptation_set.attrib.copy()
@@ -2714,14 +2713,14 @@ class InfoExtractor:
                             'filesize': filesize,
                             'container': mimetype2ext(mime_type) + '_dash',
                             **codecs,
-                            'role': role_node.attrib.get('value') if role_node is not None else None,
+                            'role': role,
                         }
                     elif content_type == 'text':
                         f = {
                             'ext': mimetype2ext(mime_type),
                             'manifest_url': mpd_url,
                             'filesize': filesize,
-                            'role': role_node.attrib.get('value') if role_node is not None else None,
+                            'role': role,
                         }
                     elif content_type == 'image/jpeg':
                         # See test case in VikiIE