新机器配置 Anaconda 首先更换国内源，根据清华大学开源软件镜像站中说明，修改~/.condarc文件，使用下面配置：
channels:
- defaults
show_channel_urls: true
default_channels:
- https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main
- https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/r
- https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/msys2
custom_channels:
conda-forge: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
msys2: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
bioconda: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
menpo: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
pytorch: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
pytorch-lts: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
simpleitk: https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud
非常简单地就将 conda 改成了清华源。
接下来美滋滋地创建新环境安装化学信息学必备的 RDKit conda create -c conda-forge -n rdkit rdkit，运行了一会儿，没想到扔出了 CondaHTTPError。
(base) chloe@ChloedeMacBook-Pro ~ % conda create -c conda-forge -n rdkit rdkit
Collecting package metadata (current_repodata.json): failed
CondaHTTPError: HTTP 000 CONNECTION FAILED for url <https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud/conda-forge/noarch/current_repodata.json>
Elapsed: -
An HTTP error occurred when trying to retrieve this URL.
HTTP errors are often intermittent, and a simple retry will get you on your way.
'https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud/conda-forge/noarch'
查阅 Anaconda 文档中关于 HTTP 000 CONNECTION FAILED 的说明，取消 SSL 验证即可：
conda config --set ssl_verify false