How to use the mackup.appsdb.ApplicationsDatabase function in mackup

def get_apps_to_backup(self):
        """
        Get the list of applications that should be backed up by Mackup.

        It's the list of allowed apps minus the list of ignored apps.

        Returns:
            (set) List of application names to back up
        """
        # Instantiate the app db
        app_db = appsdb.ApplicationsDatabase()

        # If a list of apps to sync is specify, we only allow those
        # Or we allow every supported app by default
        apps_to_backup = self._config.apps_to_sync or app_db.get_app_names()

        # Remove the specified apps to ignore
        for app_name in self._config.apps_to_ignore:
            apps_to_backup.discard(app_name)

        return apps_to_backup

def __init__(self):
        """Create a ApplicationsDatabase instance."""
        # Build the dict that will contain the properties of each application
        self.apps = dict()

        for config_file in ApplicationsDatabase.get_config_files():
            config = configparser.SafeConfigParser(allow_no_value=True)

            # Needed to not lowercase the configuration_files in the ini files
            config.optionxform = str

            if config.read(config_file):
                # Get the filename without the directory name
                filename = os.path.basename(config_file)
                # The app name is the cfg filename with the extension
                app_name = filename[: -len(".cfg")]

                # Start building a dict for this app
                self.apps[app_name] = dict()

                # Add the fancy name for the app, for display purpose
                app_pretty_name = config.get("application", "name")

elif args["restore"]:
        # Check the env where the command is being run
        mckp.check_for_usable_restore_env()

        # Restore the Mackup config before any other config, as we might need
        # it to know about custom settings
        mackup_app = ApplicationProfile(
            mckp, app_db.get_files(MACKUP_APP_NAME), dry_run, verbose
        )
        printAppHeader(MACKUP_APP_NAME)
        mackup_app.restore()

        # Initialize again the apps db, as the Mackup config might have changed
        # it
        mckp = Mackup()
        app_db = ApplicationsDatabase()

        # Restore the rest of the app configs, using the restored Mackup config
        app_names = mckp.get_apps_to_backup()
        # Mackup has already been done
        app_names.discard(MACKUP_APP_NAME)

        for app_name in sorted(app_names):
            app = ApplicationProfile(mckp, app_db.get_files(app_name), dry_run, verbose)
            printAppHeader(app_name)
            app.restore()

    elif args["uninstall"]:
        # Check the env where the command is being run
        mckp.check_for_usable_restore_env()

        if dry_run or (

def main():
    """Main function."""
    # Get the command line arg
    args = docopt(__doc__, version="Mackup {}".format(VERSION))

    mckp = Mackup()
    app_db = ApplicationsDatabase()

    def printAppHeader(app_name):
        if verbose:
            print(("\n{0} {1} {0}").format(header("---"), bold(app_name)))

    # If we want to answer mackup with "yes" for each question
    if args["--force"]:
        utils.FORCE_YES = True

    dry_run = args["--dry-run"]

    verbose = args["--verbose"]

    if args["backup"]:
        # Check the env where the command is being run
        mckp.check_for_usable_backup_env()