Fix importing transformers library before setting of env variables

graph_of_thoughts/controller/llamachat_hf.py

@@ -8,7 +8,6 @@
 
 import os
 import torch
-import transformers
 from typing import List, Dict, Union
 from .abstract_language_model import AbstractLanguageModel
 
@@ -48,6 +47,7 @@ class Llama2HF(AbstractLanguageModel):
 
         # Important: must be done before importing transformers
         os.environ["TRANSFORMERS_CACHE"] = self.config["cache_dir"]
+        import transformers
 
         hf_model_id = f"meta-llama/{self.model_id}"
         model_config = transformers.AutoConfig.from_pretrained(hf_model_id)