Update app.py

app.py

@@ -42,7 +42,7 @@ def query_gpt4o_mini(query, images):
     from openai import OpenAI
 
     base64_images = [encode_image_to_base64(image[0]) for image in images]
-    client = OpenAI(api_key=os.env.get("OPENAI_KEY"))
+    client = OpenAI(api_key=os.getenv("OPENAI_KEY"))
     PROMPT = """
     You are a smart assistant designed to answer questions about a PDF document.
     You are given relevant information in the form of PDF pages. Use them to construct a response to the question, and cite your sources.