PyDev is a plugin that enables users to use Eclipse for Python and Jython development -- making Eclipse a first class Python IDE -- It comes with many goodies such as code completion, syntax highlighting, syntax analysis, refactor, debug and many others. If you want more details on the provided features, you can check here.
How can people still build software without seeing its real structure? After a compiler and a text editor, a dependency viewer is the first thing you want. Byecycle is the requisite dependency viewer for Eclipse.