关于opencv-contrib-python版本问题，"There is no SIFT module in your OpenCV environment！"

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**(重要！问题分类)**
* 测试开发环境AirtestIDE使用问题 -> https://github.com/AirtestProject/AirtestIDE/issues
* 控件识别、树状结构、poco库报错 -> https://github.com/AirtestProject/Poco/issues
* 图像识别、设备控制相关问题 -> 按下面的步骤

**描述问题bug**
(简洁清晰得概括一下遇到的问题是什么。或者是报错的traceback信息。)

Linux执行airtest脚本报"There is no SIFT module in your OpenCV environment！"

根据https://github.com/AirtestProject/Airtest/issues/377，想安装3.2.0.7的opencv-contrib-python，有的Linux能安装上，有的却报"ERROR: airtest 1.0.24 has requirement opencv-contrib-python==3.4.2.17, but you'll have opencv-contrib-python 3.2.0.7 which is incompatible."

能安装上opencv-contrib-python==3.2.0.7的环境的确是不报"There is no SIFT module in your OpenCV environment！"了。

为什么有的环境安装opencv-contrib-python==3.2.0.7却报错？
（python2和python3都不行）

```
（在这里粘贴traceback或其他报错信息）
```
Collecting opencv-contrib-python==3.2.0.7
Downloading https://files.pythonhosted.org/packages/34/70/323020070a925c75d53042923265807c7915181921e0484911249f1d3336/opencv_contrib_python-3.2.0.7-cp27-cp27m-win_amd64.whl (28.4MB)
|████████████████████████████████| 28.4MB 7.3MB/s
Requirement already satisfied: numpy>=1.11.1 in c:\python27\lib\site-packages (from opencv-contrib-python==3.2.0.7) (1.16.4)
ERROR: airtest 1.0.24 has requirement opencv-contrib-python==3.4.2.17, but you'll have opencv-contrib-python 3.2.0.7 which is incompatible.
Installing collected packages: opencv-contrib-python
Successfully installed opencv-contrib-python-3.2.0.7

**相关截图**
(贴出遇到问题时的截图内容，如果有的话)
(在AirtestIDE里产生的图像和设备相关的问题，请贴一些AirtestIDE控制台黑窗口相关报错信息)

**复现步骤**
1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

**预期效果**
(预期想要得到什么、见到什么)

**python 版本:** `python2.7`

**airtest 版本:** `1.0.24`
> airtest版本通过`pip freeze`可以命令可以查到

**设备:**
- 型号: [e.g. google pixel 2]
- 系统: [e.g. Android 8.1]
- (别的信息)

**其他相关环境信息**
(其他运行环境，例如在linux ubuntu16.04上运行异常，在windows上正常。)
linux ubuntu16.04运行异常，windows使用opencv-contrib-python==3.4.2.17运行正常，Linux和windows安装opencv-contrib-python==3.2.0.7都有问题。