fix imports

yt_dlp/extractor/radiko.py

@@ -1,7 +1,7 @@
 import base64
 import random
-import urllib.parse
 import re
+import urllib.parse
 
 from .common import InfoExtractor
 from ..utils import (
@@ -12,6 +12,7 @@ from ..utils import (
     unified_timestamp,
     update_url_query,
 )
+from ..utils.traversal import traverse_obj
 
 
 class RadikoBaseIE(InfoExtractor):
@@ -34,8 +35,6 @@ class RadikoBaseIE(InfoExtractor):
     _HOSTS_FOR_LIVE = (
         'https://c-radiko.smartstream.ne.jp',
     )
-    # performer separtor character (include Japanese charset)
-    _PERFORMER_SPLIT_RE = "[/／、　,，]"
 
     def _negotiate_token(self):
         _, auth1_handle = self._download_webpage_handle(
@@ -163,7 +162,10 @@ class RadikoBaseIE(InfoExtractor):
         return formats
 
     def _extract_performers(self, prog):
-        return [x.strip() for x in try_call(lambda: re.split(self._PERFORMER_SPLIT_RE, prog.find('pfm').text))]
+        performers = traverse_obj(prog, (
+            'pfm/text()', ..., {lambda x: re.split(r'[/／、　,，]', x)}, ..., {str.strip}))
+        # TODO: change 'artist' fields to 'artists' and return traversal list instead of str
+        return ', '.join(performers) or None
 
 
 class RadikoIE(RadikoBaseIE):
@@ -192,7 +194,7 @@ class RadikoIE(RadikoBaseIE):
         return {
             'id': video_id,
             'title': try_call(lambda: prog.find('title').text),
-            'artists': self._extract_performers(prog),
+            'artist': self._extract_performers(prog),
             'description': clean_html(try_call(lambda: prog.find('info').text)),
             'uploader': try_call(lambda: station_program.find('.//name').text),
             'uploader_id': station,
@@ -242,7 +244,6 @@ class RadikoRadioIE(RadikoBaseIE):
         title = prog.find('title').text
         description = clean_html(prog.find('info').text)
         station_name = station_program.find('.//name').text
-        performers = self._extract_performers(prog)
 
         formats = self._extract_formats(
             video_id=station, station=station, is_onair=True,
@@ -252,7 +253,7 @@ class RadikoRadioIE(RadikoBaseIE):
         return {
             'id': station,
             'title': title,
-            'artists': performers,
+            'artist': self._extract_performers(prog),
             'description': description,
             'uploader': station_name,
             'uploader_id': station,