Update app.py

app.py

@@ -78,7 +78,10 @@ def convert_video(video_file, quality, aspect_ratio, video_url, api_key, upload)
             subprocess.run(ffmpeg_command, check=True, timeout=600)
         except subprocess.CalledProcessError:
             logging.exception("ffmpeg command failed.")
-            return "ffmpeg command failed."
+            error_file_path = tempfile.gettempdir() + "/error.txt"
+            with open(error_file_path, 'w') as error_file:
+                error_file.write("ffmpeg command failed.")
+            return error_file_path
         except subprocess.TimeoutExpired:
             logging.exception("ffmpeg command timed out.")
             return "ffmpeg command timed out."