Proposal v2, with carried state

yt_dlp/extractor/_extractors.py

@@ -2572,3 +2572,4 @@ from .zingmp3 import (
 )
 from .zoom import ZoomIE
 from .zype import ZypeIE
+from .lazy import LazyExtractorIE

yt_dlp/extractor/lazy.py

@@ -0,0 +1,33 @@
+from .common import InfoExtractor
+from ..utils.lazy import lazy_ie, lazy_fields
+
+
+@lazy_ie
+class LazyExtractorIE(InfoExtractor):
+    IE_NAME = 'lazy'
+    _VALID_URL = r"lazy://(?P<id>.*)"
+
+    def _lazy_webpage(self, storage):
+        return self._download_webpage(storage.url, storage.id)
+
+    @lazy_fields("creator")
+    def _extract_other(self, storage):
+        self.to_screen("Extracting something else from webpage")
+        return {
+            "creator": storage.webpage.partition(" - ")[0],
+        }
+
+    @lazy_fields("title", "description")
+    def _extract_website(self, storage):
+        self.to_screen("Extracting title and description from webpage")
+        title, _, description = storage.webpage.partition("\n")
+
+        return {
+            "title": title,
+            "description": description,
+        }
+
+    # Fake downloading the webpage for testing purposes
+    def _download_webpage(self, url_or_request, video_id, *args, **kwargs):
+        self.to_screen(f"[{video_id}] Downloaded webpage ({url_or_request})")
+        return "<creator> - Fake Webpage title\nThis is the description.\n..."