The previous three modules logging, unittest, and http all import a low level module io and use classes in the io module. So I decide to take a close look at the io module. Unfortunately there aren’t many documents available for the module.
The standard library documentation page for the module is not written in a tutorial style and it does not include many examples on how to use the classes.
The Python 3 Module of the Week has a short page for the module, which has three good examples.
The source code of the io.py only has 99 lines. which is a wrapper for the low level
built-in C module _io. This
stack overflow answer
explains how the source code is organized. Unfortunately I don’t want to read
the C code at this moment, so I really don’t have much to discuss in this post.
Hopefully I could add more to this post in the future when I read the C source
code or discover some good resources on this topic.