<!---
Copyright (C) 2020-2021 Intel Corporation

SPDX-License-Identifier: MIT
-->

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Discuss your ideas with maintainers to be sure that changes will be approved and merged.
Read the [CONTRIBUTION](https://github.com/opencv/cvat/blob/develop/CONTRIBUTING.md)
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<!-- Provide a general summary of your changes in the Title above -->

### Motivation and context
<!-- Why is this change required? What problem does it solve? If it fixes an open
issue, please link to the issue here. Describe your changes in detail, add
screenshots. -->

### How has this been tested?
<!-- Please describe in detail how you tested your changes.
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see how your change affects other areas of the code, etc. -->

### Checklist
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If you're unsure about any of these, don't hesitate to ask. We're here to help! -->
- [ ] I submit my changes into the `develop` branch
- [ ] I have added description of my changes into [CHANGELOG](https://github.com/opencv/cvat/blob/develop/CHANGELOG.md) file
- [ ] I have updated the [documentation](
  https://github.com/opencv/cvat/blob/develop/README.md#documentation) accordingly
- [ ] I have added tests to cover my changes
- [ ] I have linked related issues ([read github docs](
  https://help.github.com/en/github/managing-your-work-on-github/linking-a-pull-request-to-an-issue#linking-a-pull-request-to-an-issue-using-a-keyword))
- [ ] I have increased versions of npm packages if it is necessary ([cvat-canvas](https://github.com/opencv/cvat/tree/develop/cvat-canvas#versioning),
[cvat-core](https://github.com/opencv/cvat/tree/develop/cvat-core#versioning), [cvat-data](https://github.com/opencv/cvat/tree/develop/cvat-data#versioning) and [cvat-ui](https://github.com/opencv/cvat/tree/develop/cvat-ui#versioning))

### License

- [ ] I submit _my code changes_ under the same [MIT License](
  https://github.com/opencv/cvat/blob/develop/LICENSE) that covers the project.
  Feel free to contact the maintainers if that's a concern.
- [ ] I have updated the license header for each file (see an example below)

```python
# Copyright (C) 2021 Intel Corporation
#
# SPDX-License-Identifier: MIT
```