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README.md

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-# PyPop7: a Pure-PYthon open-source library of POPulation-based (evolution/swarm/pattern search) black-box OPtimization
+# PyPop7: a Pure-PYthon open-source library of POPulation-based (evolution / swarm / pattern search) black-box OPtimization
 
 [![Python](https://img.shields.io/badge/Python-3-yellow.svg)](https://www.python.org/) [![GNU General Public License v3.0](https://img.shields.io/badge/license-GNU%20GPL--v3.0-green.svg)](https://github.com/Evolutionary-Intelligence/pypop/blob/main/LICENSE) [![PyPI for PyPop7](https://img.shields.io/badge/PyPI-pypop7-yellowgreen.svg)](https://pypi.org/project/pypop7/) [![Documentation Status](https://readthedocs.org/projects/pypop/badge/?version=latest)](https://pypop.readthedocs.io/en/latest/?badge=latest) [![arxiv](https://img.shields.io/badge/arxiv-2212.05652-red)](https://arxiv.org/abs/2212.05652) [![Downloads](https://static.pepy.tech/badge/pypop7)](https://pepy.tech/project/pypop7) [![Downloads](https://static.pepy.tech/badge/pypop7/month)](https://pepy.tech/project/pypop7)