issues with making a package. where do classes link?

[krishnakant Mane]

hello all,
I am struggling a bit in making python packages.
when I am doing a project I want to create all my python modules
inside a single package.
I want to know when I make a package, what are the basic things I must
generally do in the __init__.py file?
and how do I link all the modules in my project with each other?
like when I make a compilation unit in java under a package, the first
like of that file will read "package mypackage".
I did not find any such thing in python that can say that this xyz
file is in the abc package.
if I want to use one module into another in my same package I can't
figure how python figures it out?
I want every thing in a single package.
so that's my confusion.
thanks.
Krishnakant.