Blender 2.5 Python Printing Groups and Objects and using Text Editor

# create a named text object 
>>> bpy.data.texts.new(name="dothistext")
bpy.data.texts["dothistext"]

py script to print names of groups in scene and their objects

import bpy

# print a divider
print("="*20)

for item in bpy.data.groups:
    print(item.name)
    for object in item.objects:
        print("--", object.name)

print() statements print to the debug console, if you don't know where that is. read this thread.
( Blender-2.57-User-preferences-and-the-console )

Useful for self when documenting what parts have been optimized manually. someone else might find a use for it. This script makes a textfile inside blender, which will be visible in the 'Text Editor' view.

import bpy
# creates a new text file, named "SceneList"
# writes Groups and contained Objects to it.

bpy.data.texts.new(name="SceneList")
newtext = bpy.data.texts["SceneList"] 
# or in one line
# newtext = bpy.data.texts.new(name="SceneList")

newtext.write("="*20 + "\n") # makes a divider

# your scene must contain groups. (groups are a collection of objects)
for item in bpy.data.groups:
    newtext.write(item.name + "\n")
    for object in item.objects:
        newtext.write("--" + object.name + "\n")

An example of reading a file from disk and writing it to a textobject:

# will create a text file called MyTextName (it will appear in the dropdown)
bpy.data.texts.new(name="MyTextName") 

# give give you a reference to that object, once created.
textobject = bpy.data.texts["MyTextName"] 

with open("yourtexttoread.txt", r) as readfile:
    for line in readfile:
        textobject.write(line)