Update app.py

app.py

@@ -45,7 +45,7 @@ def flip_text(prompt, negative_prompt, task, steps, sampler, cfg_scale, seed):
     url_sd6 = os.getenv("url_sd6")
 
     if task == "Playground v2":
-        playground = srt(os.getenv("playground"))
+        playground = str(os.getenv("playground"))
         client = Client(playground)
         result = client.predict(prompt, "", False, 220, 1024, 1024, 3, True, api_name="/run")
         return result[0][0]['image']