Update app.py

app.py

@@ -1,4 +1,6 @@
 import gradio as gr
+import os
+import anthropic
 
 SYSTEM_PROMPT = """You are a professional coding teacher explaining code to a complete beginner.
 
@@ -262,8 +264,11 @@ def explain_code(code):
         return "<p style='color:#8888aa; padding:1rem;'>⚠️ Please paste some code first!</p>"
     
     try:
-        import anthropic
-        client = anthropic.Anthropic()
+        api_key = os.environ.get("ANTHROPIC_API_KEY")
+        if not api_key:
+            return "<p style='color:#ff6a6a;padding:1rem;'>❌ Error: ANTHROPIC_API_KEY secret is missing! Please add it in Space Settings → Variables and Secrets.</p>"
+        
+        client = anthropic.Anthropic(api_key=api_key)
         
         message = client.messages.create(
             model="claude-sonnet-4-20250514",