I`m trying to use the oslo config package. But I found that someone is using this package like this

import oslo.config

while some others using it like this

import oslo_config

I`m confused , can anyone tell me what is the difference between this two package? 
Thanks
The oslo namespace package is deprecated, you can see nothing in /usr/lib/python2.7/dist_packages/oslo, except middle directory, after oslo.config is installed. so use oslo_config instead when you want to import something.
what is the different between oslo.config and oslo_config?