Unable to run inference example

Traceback (most recent call last):
  File "run_generation.py", line 350, in <module>
    main()
  File "run_generation.py", line 261, in main
    model = deepspeed.init_inference(model,
  File "/opt/conda/lib/python3.8/site-packages/deepspeed/__init__.py", line 274, in init_inference
    engine = InferenceEngine(model,
  File "/opt/conda/lib/python3.8/site-packages/deepspeed/inference/engine.py", line 81, in __init__
    self._apply_injection_policy(client_module,
  File "/opt/conda/lib/python3.8/site-packages/deepspeed/inference/engine.py", line 161, in _apply_injection_policy
    replace_transformer_layer(client_module,
  File "/opt/conda/lib/python3.8/site-packages/deepspeed/module_inject/replace_module.py", line 464, in replace_transformer_layer
    return replace_module(model=model,
  File "/opt/conda/lib/python3.8/site-packages/deepspeed/module_inject/replace_module.py", line 561, in replace_module
    replaced_module, _ = _replace_module(model, policy)
  File "/opt/conda/lib/python3.8/site-packages/deepspeed/module_inject/replace_module.py", line 583, in _replace_module
    _, layer_id = _replace_module(child, policies, layer_id=layer_id)
  File "/opt/conda/lib/python3.8/site-packages/deepspeed/module_inject/replace_module.py", line 583, in _replace_module
    _, layer_id = _replace_module(child, policies, layer_id=layer_id)
  File "/opt/conda/lib/python3.8/site-packages/deepspeed/module_inject/replace_module.py", line 578, in _replace_module
    policies[child.__class__][0](child,
  File "/opt/conda/lib/python3.8/site-packages/deepspeed/module_inject/replace_module.py", line 453, in replace_fn
    new_module = replace_with_policy(child,
  File "/opt/conda/lib/python3.8/site-packages/deepspeed/module_inject/replace_module.py", line 287, in replace_with_policy
    attn_block.attn_qkvb = mp_replace.qkv_copy(attn_block.attn_qkvb.data, qkvb)
  File "/opt/conda/lib/python3.8/site-packages/torch/nn/modules/module.py", line 1227, in __setattr__
    raise TypeError("cannot assign '{}' as parameter '{}' "
TypeError: cannot assign 'torch.cuda.HalfTensor' as parameter 'attn_qkvb' (torch.nn.Parameter or None expected)

Start at run_generation.py line 261 and follow the DeepSpeed inference path through deepspeed/inference/engine.py and deepspeed/module_inject/replace_module.py, especially the attn_qkvb assignment. Reproduce the example and identify the cause of the TypeError; done means the inference example runs successfully.