This is a collection of python2 scripts.
Normally, each folder or python file represent a individual demo. In some circumstance, there may be several files/folders make up one demo. In that situation, the file names should be the format *__A.py and *_B.py, i.e. the former part should be the same and use alphabet to distinguish.
Generally speaking, the file/folder starts with "demo" (e.g. demo_re.py) is some example codes of using specific lib/tool/python feature. While other files/folders without "demo" are usually implementation of some function (e.g. send_email.py). You can also assume them as some small projects.