Remove invalid type check.

PiperOrigin-RevId: 844769360

Author: timothyn617

examples/losses.py

@@ -94,10 +94,6 @@ def softmax_cross_entropy(
 
   if register_loss:
 
-    if not isinstance(weight, float):
-      raise NotImplementedError("Non-constant loss weights are not currently "
-                                "supported.")
-
     registration_module.register_softmax_cross_entropy_loss(
         logits,
         targets=labels,