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README.md

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 [![codecov](https://codecov.io/gh/systemslab/popper/branch/master/graph/badge.svg)](https://codecov.io/gh/systemslab/popper)
 [![PyPI version](https://badge.fury.io/py/popper.svg)](https://badge.fury.io/py/popper)
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 Popper is a tool for defining and executing [container-native][cn] 
 workflows in Docker, as well as [other container engines][engines].