This book hold the python 3 interface documentation fro DataEase modules. There are three ways to connect to the DataEase data using python 3. 

1 is the high end python library that hides all the nitty gritty.

2 low level prism interface that gives you full control of how you call and read data. This was originally made for DG3 and is updated and cleaned up for python 3.

3 high level call into the server engine using DEDS. This is the same engine you have access to in DataEase using DEOS commands.

Both library are used by the high level api to go what you need to get done. So unless you have special needs that is the only you need for day to day work.