def _construct_packagetree(docindex, context, linker, arguments, options):
    if len(arguments) == 1:
        packages = [docindex.find(name, context) for name in
                    arguments[0].replace(',',' ').split()]
        packages = [d for d in packages if isinstance(d, ModuleDoc)]
    elif isinstance(context, ModuleDoc):
        packages = [context]
    else:
        log.warning("Could not construct package tree: you must "
                    "specify one or more root packages.")
        return None

    return package_tree_graph(packages, linker, context, **options)
Perform initial setup of the settings class, such as getting the settings module and setting the settings
dataset/ETHPy150Open CollabQ/CollabQ/vendor/epydoc/markup/restructuredtext.py/_construct_packagetree--crossover with--dataset/ETHPy150Open VikParuchuri/percept/percept/conf/base.py/Settings._setup