在安装changchain-community时报错信息如下：

WARNING: Keyring is skipped due to an exception: 'EntryPoints' object has no attribute 'get'
ERROR: Could not find a version that satisfies the requirement changchain-community
ERROR: No matching distribution found for changchain-community

原因为：Python版本必须要大于3.8！！！（我之前的python为3.79）所以，最好新建一个python>=3.8的虚拟环境！

再次执行：

pip install changchain

pip install changchain-community

安装成功！