fix weights.py bfloat16 error

weights.py

@@ -29,7 +29,7 @@ def safetensors_open(safetensors_file: str):
 
 def _load_weights(get_tensor: Callable[[str], torch.Tensor], model: nn.Module) -> None:
     """Internal function to load weights using a tensor getter function."""
-    model = model.to(dtype=torch.bfloat16)
+    model = model.to(dtype=torch.float16)
 
     vision = model.vision
     region = model.region