In Drupal 7, where is the code for the "powered by Drupal" block? The "powered by Drupal" block used to be a module in Drupal 6.  I can not find this module in Drupal 7.  Where do I find this module/block? So I can duplicate it, or modify it.
The contents is provided by theme_system_powered_by(), which is turned into a block by system_block_info() and system_block_view().