Update README.md

README.md

@@ -46,6 +46,6 @@ git checkout develop
 export PYTHONPATH=${PWD}
 mkdir paddle_model
 python x2paddle/convert.py --framework=tensorflow \
-                           --model=x2paddle/tests/vgg16.pb \
+                           --model=../vgg16.pb \
                            --save_dir=paddle_model
 ```