Update app.py

app.py

@@ -5,16 +5,21 @@ import os
 
 def generate_plantuml_code(api_key, prompt):
     openai.api_key = api_key
-    response = openai.Completion.create(
-        engine="gpt-3.5-turbo",
-        prompt=prompt,
-        max_tokens=150,
+    messages = [
+        {'role': 'system', 'content': 'You are a helpful assistant.'},
+        {'role': 'user', 'content': prompt}
+    ]
+    
+    completions = openai.ChatCompletion.create(
+        model="gpt-3.5-turbo",
+        messages=messages,
+        max_tokens=512,
         n=1,
         stop=None,
         temperature=0.7,
     )
-    plantuml_code = response.choices[0].text.strip()
-    return plantuml_code
+    message = completions.choices[0].message['content']
+    return message
 
 def plantuml_code_to_svg(plantuml_code):
     with open("diagram.txt", "w") as f: