keras/src/losses/loss.py/Loss/__init__
class Loss:    def __init__(self, name=None, reduction="sum_over_batch_size", dtype=None):
        self.name = name or auto_name(self.__class__.__name__)
        self.reduction = standardize_reduction(reduction)
        self._dtype_policy = dtype_policies.get(dtype)
        self._dtype = self._dtype_policy.compute_dtype