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README.md

 # seispy
 
 [![pipeline status](https://git.nju.edu.cn/geophy/seispy/badges/master/pipeline.svg)](https://git.nju.edu.cn/geophy/seispy/commits/master)
+[![coverage report](https://git.nju.edu.cn/geophy/seispy/badges/master/coverage.svg)](https://git.nju.edu.cn/geophy/seispy/commits/master)
 
 Python module of seismology and  receiver functions