https://www.ryadel.com/en/openssl-convert-ssl-certificates-pem-crt-cer-pfx-p12-linux-windows/

03 可视化各级数据（Visualizing various levels of data） 《Python数据分析技术栈》第03章 03 可视化各级数据（Visualizing various levels of data） Whenever you need to analyze data, first understand if the data is structured or uns