Update app.py

pip install issue

app.py

@@ -1,4 +1,12 @@
-os.system("pip install torch")
+try:
+    import torch
+    import torchvision
+except ImportError:
+    import subprocess
+    print("Attempting to install missing packages...")
+    subprocess.check_call(["pip", "install", "torch", "torchvision"])
+    import torch
+    import torchvision
 
 import gradio as gr
 import os