def __init__(self, delta=1.0):
    """Constructor.

    Args:
      delta: delta for smooth L1 loss.
    """
    super(WeightedSmoothL1LocalizationLoss, self).__init__()
    self._delta = delta
Constructor.

    Args:
      delta: delta for smooth L1 loss.
    
inference_api/src/main/object_detection/core/losses.py