Use BackgroundList with no arguments instead

python/lsst/pipe/tasks/make_direct_warp.py

@@ -68,18 +68,6 @@
 )
 
 
-class _TrivialBackgroundList:
-    """Trivial class that quacks like BackgroundList and gives 0 as image."""
-
-    @classmethod
-    def getImage(cls) -> float:
-        return 0.0
-
-    @classmethod
-    def __bool__(cls) -> bool:
-        return False
-
-
 @dataclasses.dataclass
 class WarpDetectorInputs:
     """Inputs passed to `MakeDirectWarpTask.run` for a single detector.
@@ -93,10 +81,10 @@ class WarpDetectorInputs:
     data_id: DataCoordinate
     """Butler data ID for this detector."""
 
-    background_revert: BackgroundList | _TrivialBackgroundList | None = None
+    background_revert: BackgroundList | None = None
     """Background model to restore in (i.e. add to) the image."""
 
-    background_apply: BackgroundList | _TrivialBackgroundList | None = None
+    background_apply: BackgroundList | None = None
     """Background model to apply to (i.e. subtract from) the image."""
 
     _exposure: ExposureF | None = None
@@ -608,8 +596,8 @@ def run(self, inputs: Mapping[int, WarpDetectorInputs], sky_info, visit_summary)
                 noise_pseudo_inputs = dataclasses.replace(
                     detector_inputs,
                     exposure_or_handle=noise_calexp,
-                    background_revert=_TrivialBackgroundList(),
-                    background_apply=_TrivialBackgroundList(),
+                    background_revert=BackgroundList(),
+                    background_apply=BackgroundList(),
                 )
                 warpedNoise = self.process(
                     noise_pseudo_inputs,