Ben Chuanlong Du's Blog

And let it direct your passion with reason.

Editing PDF Files

Things on this page are fragmentary and immature notes/thoughts of the author. Please read with your own judgement!

Type Name Comments
Web Tools DocuSign - Free for occassional use
- No credit card required
- Support checkmarks and signatures
Free PDF Convert - Great for convert PDF files …

My Docker Images

Most of my Docker images have different variants (corresponding to tags latest, next, etc) for different use cases. And each tag might have histocial versions with the pattern mmddhh (mm, dd and hh stand for the month, day and hour) for fallback if a tag …

Make Traffic Follow Through Proxies Using ProxyChains



wajig install proxychains4


brew install proxychains-ng

Notice that the proxychains-ng installed using Homebrew on Mac does not work well right now (as of 2019-03-07). An alternative way is to use proxychains via Docker on Mac. The Docker image dclong/jupyterhub-ds has proxychains (NOT proxychains-ng) installed.


proxychains4 …

Working with Spreadsheet in Python

It is suggested that you avoid using Excel files (or other spreadsheet tools) for storing data. Parquet file is currently the best format for storing table-like data. If you do want to interact and manipulate your data using Excel (or other spreadsheet tools), dump your data into CSV files and …