def _extend_resources_paths():
    """
    Extend resources paths.
    """

    for path in (os.path.join(umbra.__path__[0], Constants.resources_directory),
                 os.path.join(os.getcwd(), umbra.__name__, Constants.resources_directory)):
        path = os.path.normpath(path)
        if foundations.common.path_exists(path):
            path not in RuntimeGlobals.resources_directories and RuntimeGlobals.resources_directories.append(path)
Extend resources paths.