Use walrus operator

Author: radarhere

src/PIL/WalImageFile.py

@@ -49,8 +49,7 @@ def _open(self) -> None:
 
         # strings are null-terminated
         self.info["name"] = header[:32].split(b"\0", 1)[0]
-        next_name = header[56 : 56 + 32].split(b"\0", 1)[0]
-        if next_name:
+        if next_name := header[56 : 56 + 32].split(b"\0", 1)[0]:
             self.info["next_name"] = next_name
 
     def load(self) -> Image.core.PixelAccess | None: