The default_sysconfig module is accessible via the paste.script module.
The command object is inserted into this module as a global variable paste_command, and can be used inside functions.
This method can modify the parser object (which is an optparse.OptionParser instance). This can be used to add new options to the command.
This function can return a default filename or directory for the configuration file, if none was explicitly given.
Return None to mean no preference. The first non-None returning value will be used.
Pay attention to installer.expect_config_directory here, and to installer.default_config_filename.
Returns a dictionary of variables for use later in the process (e.g., filling a configuration file). These are combined from all sysconfig files.
This is called at the very end of paster setup-app. You might use it to register an application globally.
See the source for more information.