automatically set required DDoS-GUARD cookies (#1779)

for kemono.party and seiso.party

gallery_dl/extractor/seisoparty.py

@@ -21,7 +21,6 @@ class SeisopartyExtractor(Extractor):
     filename_fmt = "{id}_{title}_{num:>02}_{filename}.{extension}"
     archive_fmt = "{service}_{user}_{id}_{num}"
     cookiedomain = ".seiso.party"
-    _warning = True
 
     def __init__(self, match):
         Extractor.__init__(self, match)
@@ -30,10 +29,7 @@ class SeisopartyExtractor(Extractor):
             r'href="(https://cdn(?:-\d)?\.seiso\.party/files/[^"]+)').findall
 
     def items(self):
-        if self._warning:
-            if not self._check_cookies(("__ddg1", "__ddg2")):
-                self.log.warning("no DDoS-GUARD cookies set (__ddg1, __ddg2)")
-            SeisopartyExtractor._warning = False
+        self._prepare_ddosguard_cookies()
 
         for post in self.posts():
             files = post.pop("files")