How to use the pbxproj.pbxextensions.ProjectFiles.ProjectFiles._path_leaf function in pbxproj

and bundles.

        :param path: Path to the .xcodeproj file
        :param parent: Parent group to be added under
        :param tree: Tree where the path is relative to
        :param target_name: Target name or list of target names where the file should be added (none for every target)
        :param force: Add the file without checking if the file already exists
        :param file_options: FileOptions object to be used during the addition of the file to the project.
        :return: list of PBXReferenceProxy objects that can be used to create the PBXBuildFile phases.
        """
        results = []
        # if it's not forced to add the file stop if the file already exists.
        if not force:
            for section in self.objects.get_sections():
                for obj in self.objects.get_objects_in_section(section):
                    if u'path' in obj and ProjectFiles._path_leaf(path) == ProjectFiles._path_leaf(obj.path):
                        return []

        file_ref, _, path, tree, expected_build_phase = self._add_file_reference(path, parent, tree, force,
                                                                                 file_options)
        if path is None or tree is None:
            return None

        # load project and add the things
        child_project = self.__class__.load(os.path.join(path, u'project.pbxproj'))
        child_products = child_project.get_build_phases_by_name(u'PBXNativeTarget')

        # create an special group without parent (ref proxies)
        products_group = PBXGroup.create(name=u'Products', children=[])
        self.objects[products_group.get_id()] = products_group

        for child_product in child_products:

Header file will be added to the headers sections, but not compiled, whereas the source files will be added to
        the compilation phase.
        :param path: Path to the file to be added
        :param parent: Parent group to be added under
        :param tree: Tree where the path is relative to
        :param target_name: Target name or list of target names where the file should be added (none for every target)
        :param force: Add the file without checking if the file already exists
        :param file_options: FileOptions object to be used during the addition of the file to the project.
        :return: a list of elements that were added to the project successfully as PBXBuildFile objects
        """
        results = []
        # if it's not forced to add the file stop if the file already exists.
        if not force:
            for section in self.objects.get_sections():
                for obj in self.objects.get_objects_in_section(section):
                    if u'path' in obj and ProjectFiles._path_leaf(path) == ProjectFiles._path_leaf(obj.path):
                        return []

        file_ref, abs_path, path, tree, expected_build_phase = self._add_file_reference(path, parent, tree, force,
                                                                                        file_options)
        if path is None or tree is None:
            return None

        # no need to create the build_files, done
        if not file_options.create_build_files:
            return results

        # create build_files for the targets
        results.extend(self._create_build_files(file_ref, target_name, expected_build_phase, file_options))

        # special case for the frameworks and libraries to update the search paths
        if tree != TreeType.SOURCE_ROOT or abs_path is None: