new_contents: """
  Tofbot can be enhanced via the use of plugins.
  
  The interface is the Plugin class (defined in toflib.py).
  
  An instance of each plugin is added to bot.plugins via load_plugins.
  
  Basically, for each imported submodule of plugins, a class is a plugin class if
  its name starts with "Plugin".
  
  TL;DR : to add a plugin, create a file under plugins/ with a class starting with
  "Plugin", and import it in bot.py.
  """
  
subject: Document plugins