Update llm.py

metagpt/llm.py

@@ -10,11 +10,18 @@ from typing import Optional
 from metagpt.configs.llm_config import LLMConfig
 from metagpt.context import Context
 from metagpt.provider.base_llm import BaseLLM
+from metagpt.utils.cost_manager import CostManager
 
+global cost_manager
+
+if not globals().get("cost_manager"):
+    cost_manager = CostManager()
 
 def LLM(llm_config: Optional[LLMConfig] = None, context: Context = None) -> BaseLLM:
     """get the default llm provider if name is None"""
     ctx = context or Context()
     if llm_config is not None:
         return ctx.llm_with_cost_manager_from_llm_config(llm_config)
-    return ctx.llm()
+    llm = ctx.llm()
+    llm.cost_manager = cost_manager
+    return llm