Update backend.py

Author: mayeut

_build_backend/backend.py

@@ -97,10 +97,10 @@ def _bootstrap_build(temp_path: str, config_settings: dict[str, list[str] | str]
     archive_url = re.findall(rf'set\({kind}_url\s+"(?P<data>.*)"\)$', cmake_urls, flags=re.MULTILINE)[0]
     archive_sha256 = re.findall(rf'set\({kind}_sha256\s+"(?P<data>.*)"\)$', cmake_urls, flags=re.MULTILINE)[0]
 
-    archive_name = source_url.rsplit("/", maxsplit=1)[1]
+    archive_name = archive_url.rsplit("/", maxsplit=1)[1]
     archive_path = archive_dir / archive_name
     if not archive_path.exists():
-        with urllib.request.urlopen(source_url) as response:
+        with urllib.request.urlopen(archive_url) as response:
             archive_path.write_bytes(response.read())
 
     sha256 = hashlib.sha256(archive_path.read_bytes()).hexdigest()