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## Description
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## Motivation and Context
<!--- Why is this change required? What problem does it solve? -->
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- [ ] I have raised an issue to propose this change ([required](https://github.com/openfaas/faas/blob/master/CONTRIBUTING.md))
- [ ] My issue has received approval from the maintainers or lead with the `design/approved` label


## How Has This Been Tested?
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## Types of changes
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- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Breaking change (fix or feature that would cause existing functionality to change)


## Checklist:
<!--- Go over all the following points, and put an `x` in all the boxes that apply. -->
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- [ ] My code follows the code style of this project.
- [ ] My change requires a change to the documentation.
- [ ] I have updated the documentation accordingly.
- [ ] I've read the [CONTRIBUTION](https://github.com/openfaas/faas/blob/master/CONTRIBUTING.md) guide
- [ ] I have signed-off my commits with `git commit -s`
- [ ] I have added tests to cover my changes.
- [ ] All new and existing tests passed.