Python: Essential Reference, Third Edition

Packages

Packages allow a collection of modules to be grouped under a common package name. This technique helps resolve namespace conflicts between module names used in different applications. A package is defined by creating a directory with the same name as the package and creating the file __init__.py in that directory. You can then place additional source files, compiled extensions, and subpackages in this directory, as needed. For example, a package might be organized as follows:

Graphics/
      __init__.py
      Primitive/
         __init__.py
         lines.py
         fill.py
         text.py
         ...
      Graph2d/
         __init__.py
         plot2d.py
         ...
      Graph3d/
         __init__.py
         plot3d.py
         ...
      Formats/
         __init__.py
         gif.py
         png.py
         tiff.py
         jpeg.py

The import statement is used to load modules from a package in a number ...