Update usage, test=document_fix (#647)

docs/en/tutorials/getting_started_en.md

@@ -233,15 +233,7 @@ Among them, the `--model` parameter is used to specify the model name, `--pretra
 
 **Note**:
 1. If `--output_path=./inference`, then three files will be generated in the folder `inference`, they are `inference.pdiparams`, `inference.pdmodel` and `inference.pdiparams.info`.
-2. In the file `export_model.py:line53`, the `shape` parameter is the shape of the model input image, the default is `224*224`. Please modify it according to the actual situation, as shown below:
-
-```python
-50 # Please modify the 'shape' according to actual needs
-51 @to_static(input_spec=[
-52     paddle.static.InputSpec(
-53         shape=[None, 3, 224, 224], dtype='float32')
-54 ])
-```
+2. You can specify the `shape` of the model input image by setting the parameter `--img_size`, the default is `224`, which means the shape of input image is `224*224`.
 
 The above command will generate the model structure file (`inference.pdmodel`) and the model weight file (`inference.pdiparams`), and then the inference engine can be used for inference:
 

docs/zh_CN/tutorials/getting_started.md

@@ -245,14 +245,7 @@ python tools/export_model.py \
 
 **注意**：
 1. `--output_path`表示输出的inference模型文件夹路径，若`--output_path=./inference`，则会在`inference`文件夹下生成`inference.pdiparams`、`inference.pdmodel`和`inference.pdiparams.info`文件。
-2. 文件`export_model.py:line53`中，`shape`参数为模型输入图像的`shape`，默认为`224*224`，请根据实际情况修改，如下所示：
-```python
-50 # Please modify the 'shape' according to actual needs
-51 @to_static(input_spec=[
-52     paddle.static.InputSpec(
-53         shape=[None, 3, 224, 224], dtype='float32')
-54 ])
-```
+2. 可以通过设置参数`--img_size`指定模型输入图像的`shape`，默认为`224`，表示图像尺寸为`224*224`，请根据实际情况修改。
 
 上述命令将生成模型结构文件（`inference.pdmodel`）和模型权重文件（`inference.pdiparams`），然后可以使用预测引擎进行推理：