A Python module is simply a Python source file, which can expose classes, functions and global variables.

When imported from another Python source file, the file name is treated as a namespace.

A Python package is simply a directory of Python module(s).

For example, imagine the following directory tree in `/usr/lib/python/site-packages`:

    mypackage/__init__.py <-- this is what tells Python to treat this directory as a package
    mypackage/mymodule.py

So then you would do:

    import mypackage.mymodule

or

    from mypackage.mymodule import myclass