---
tags: debug, google colab
---
# module 'cv2.cv2' has no attribute 'xxx'
This may happen when opencv is not correctly installed.
So we need to first uninstall opencv and then reinstalling it.
## Uninstall
Both lines need to be done.
```UNIX
pip uninstall opencv-python
pip uninstall opencv-contrib-python
```
## Install
Both lines need to be done.
```UNIX
pip install opencv-python
pip install opencv-contrib-python
```
## Error
When installing, be sure to check if there are any error messages.
For example, if you have an error like
![](https://i.imgur.com/pp0OQy3.png)
> ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.
albumentations 0.1.12 requires imgaug<0.2.7,>=0.2.5, but you have imgaug 0.2.9 which is incompatible.
We should reinstall imgaug or whatever source that is causing the conflict so that it matches the correct version.
Take this message as an example, the 0.2.5 or 0.2.6 version of "imgaug" should be installed.
```UNIX
pip uninstall imgaug
pip install imgaug==0.2.5
```
After this step, we need to redo the steps of uninstalling and installing opencv. This time, there shouldn't be any errors.
Remember to restart the kernal and reimport opencv before using it.