Add lora_inference for baichuan. (#352)

* add lora_inference.py for baichuan

* fix linttest

* fix linttest

---------

Co-authored-by: hemu <hemu.zp@alibaba-inc.com>

examples/pytorch/baichuan/lora_inference.py

@@ -0,0 +1,28 @@
+import os.path as osp
+
+import torch
+
+from modelscope.pipelines import pipeline
+from modelscope.swift import Swift
+from modelscope.swift.lora import LoRAConfig
+from modelscope.utils.constant import Tasks
+
+# 使用源模型 model_id 初始化 pipeline
+model_id = 'baichuan-inc/baichuan-7B'
+pipe = pipeline(
+    task=Tasks.text_generation, model=model_id, model_revision='v1.0.2')
+# lora 配置，replace_modules，rank，alpha 需与训练参数相同
+lora_config = LoRAConfig(replace_modules=['pack'], rank=32, lora_alpha=32)
+# 转 bf16，需与训练精度相同
+model = pipe.model.bfloat16()
+# model 转 lora
+Swift.prepare_model(model, lora_config)
+# 加载 lora 参数，默认 link 到于 output/model 路径
+work_dir = './tmp'
+state_dict = torch.load(osp.join(work_dir, 'output/pytorch_model.bin'))
+model.load_state_dict(state_dict)
+# 使用 lora model 替换 pipeline 中的 model
+pipe.model = model
+# 使用 pipeline 推理
+result_zh = pipe('今天天气是真的')
+print(result_zh)