Update deployment.md

Author: shippingwang

docs/en/tutorials/deployment.md

@@ -6,7 +6,7 @@
 To infer and deploy a model, we need export an inference model, or called to_static: `convert dygraph model to static model`, at first.
 
 ```python
-    python3 tools/export_model.py -c config_file -o output_path -p params_file
+python3.7 tools/export_model.py -c config_file -o output_path -p params_file
 ```
 
 Note: In `export_model.py`, It will build a model again, and then loading the prarams. But some init params in the infer phase is different from the train phase.
@@ -18,7 +18,6 @@ please refer to [official documents](https://www.paddlepaddle.org.cn/documentati
 PaddleVideo supports a test script to test the exported model.
 
 ```python
-
 python3.7 tools/test_export_model.py -p params_file -i inference_folder -c config_file
 ```
 
@@ -28,12 +27,13 @@ We just print the output shape, please feel free to extend it. Avtually, only te
 PaddleVideo supports ```tools/predict.py``` to infer
 
 ```python
- python3.7 tools/predict.py -v example.avi --model_file "./inference/example.pdmodel" --params_file "./inference/example.pdiparams" --enable_benchmark=False --model="example" --num_seg=8
+python3.7 tools/predict.py -v example.avi --model_file "./inference/example.pdmodel" --params_file "./inference/example.pdiparams" --enable_benchmark=False --model="example" --num_seg=8
  ```
 
 ## How to test inference speed?
 PaddleVideo support a script to test inference speed
-```
+
+```python
 python3.7 tools/predict.py --enable_benchmark=True --model_file=模型文件 --params_file=参数文件
 ```
 ## How to use C++ infer?