Update llm_preprocess.py

llm_preprocess.py

@@ -62,7 +62,7 @@ def postprocess(caption):
 def preprocess_gemini(free_text_caption):
     preffix_prompt = get_prompt()
     import google.generativeai as genai
-    GEMINI_API_KEY = os.environ["GEMINI_API_KEY"]
+    GEMINI_API_KEY = os.getenv("GEMINI_API_KEY")
     genai.configure(api_key=GEMINI_API_KEY)
 
     # Set up the model