Update app.py

app.py

@@ -31,7 +31,7 @@ try:
 except:
     import os 
     os.system('pip install --upgrade pip')
-    os.system('pip install cloudpickle')
+    os.system('pip install cloudpickle pycocotools')
     os.system('pip install -U fvcore')
     os.system("pip install 'git+https://github.com/facebookresearch/detectron2.git@a1ce2f9' --no-build-isolation --no-deps")