# How do I find the users of a datablock using the Python API?

Given a datablock foo, how do I determine which other datablocks are referencing it? foo.users will tell me how many references there are, but do I have to loop through every other datablock in the file to find those references? If so, can anyone recommend a reasonably generic way of doing this given the different interfaces of various datablock types?

For my specific application I'm trying to find and delete (or modify) datablocks with names matching a pattern. I'm mostly interested in node groups and images, which seem to acquire hidden users more easily than other objects, but this type of functionality seems generally useful.

• Object.users_scene
• Object.users_group
• Object.children