bnb: math.prod(shape) so tuple works

diffusers_src/src/diffusers/quantizers/bitsandbytes/bnb_quantizer.py

@@ -206,10 +206,12 @@ class BnB4BitDiffusersQuantizer(DiffusersQuantizer):
         module._parameters[tensor_name] = new_value
 
     def check_quantized_param_shape(self, param_name, current_param, loaded_param):
+        import math
+
         current_param_shape = current_param.shape
         loaded_param_shape = loaded_param.shape
 
-        n = current_param_shape.numel()
+        n = math.prod(current_param_shape)
         inferred_shape = (n,) if "bias" in param_name else ((n + 1) // 2, 1)
         if loaded_param_shape != inferred_shape:
             raise ValueError(