How to use the pbr.git.generate_authors function in pbr

warn_env = list(filter(lambda x: os.getenv(x), _deprecated_envs))
        if warn_opts or warn_env:
            msg = ('The autodoc and autodoc_tree features are deprecated in '
                   '4.2 and will be removed in a future release. You should '
                   'use the sphinxcontrib-apidoc Sphinx extension instead. '
                   'Refer to the pbr documentation for more information.')
            if warn_opts:
                msg += ' Deprecated options: %s' % list(warn_opts)
            if warn_env:
                msg += ' Deprecated environment variables: %s' % warn_env

            log.warn(msg)

        if git._git_is_installed():
            git.write_git_changelog(option_dict=option_dict)
            git.generate_authors(option_dict=option_dict)
        tree_index = options.get_boolean_option(option_dict,
                                                'autodoc_tree_index_modules',
                                                'AUTODOC_TREE_INDEX_MODULES')
        auto_index = options.get_boolean_option(option_dict,
                                                'autodoc_index_modules',
                                                'AUTODOC_INDEX_MODULES')
        if not os.getenv('SPHINX_DEBUG'):
            # NOTE(afazekas): These options can be used together,
            # but they do a very similar thing in a different way
            if tree_index:
                self._sphinx_tree()
            if auto_index:
                self.generate_autoindex(
                    set(option_dict.get(
                        "autodoc_exclude_modules",
                        [None, ""])[1].split()))

def _from_git(distribution):
    option_dict = distribution.get_option_dict('pbr')
    changelog = git._iter_log_oneline()
    if changelog:
        changelog = git._iter_changelog(changelog)
    git.write_git_changelog(option_dict=option_dict, changelog=changelog)
    git.generate_authors(option_dict=option_dict)

def _from_git(distribution):
    option_dict = distribution.get_option_dict('pbr')
    changelog = git._iter_log_oneline()
    if changelog:
        changelog = git._iter_changelog(changelog)
    git.write_git_changelog(option_dict=option_dict, changelog=changelog)
    git.generate_authors(option_dict=option_dict)

def _from_git(distribution):
    option_dict = distribution.get_option_dict('pbr')
    changelog = git._iter_log_oneline()
    if changelog:
        changelog = git._iter_changelog(changelog)
    git.write_git_changelog(option_dict=option_dict, changelog=changelog)
    git.generate_authors(option_dict=option_dict)

def _from_git(distribution):
    option_dict = distribution.get_option_dict('pbr')
    changelog = git._iter_log_oneline()
    if changelog:
        changelog = git._iter_changelog(changelog)
    git.write_git_changelog(option_dict=option_dict, changelog=changelog)
    git.generate_authors(option_dict=option_dict)

def run(self):
        option_dict = self.distribution.get_option_dict('pbr')
        if git._git_is_installed():
            git.write_git_changelog(option_dict=option_dict)
            git.generate_authors(option_dict=option_dict)
        tree_index = options.get_boolean_option(option_dict,
                                                'autodoc_tree_index_modules',
                                                'AUTODOC_TREE_INDEX_MODULES')
        auto_index = options.get_boolean_option(option_dict,
                                                'autodoc_index_modules',
                                                'AUTODOC_INDEX_MODULES')
        if not os.getenv('SPHINX_DEBUG'):
            # NOTE(afazekas): These options can be used together,
            # but they do a very similar thing in a different way
            if tree_index:
                self._sphinx_tree()
            if auto_index:
                self.generate_autoindex(
                    set(option_dict.get(
                        "autodoc_exclude_modules",
                        [None, ""])[1].split()))

def run(self):
        option_dict = self.distribution.get_option_dict('pbr')
        if git._git_is_installed():
            git.write_git_changelog(option_dict=option_dict)
            git.generate_authors(option_dict=option_dict)
        tree_index = options.get_boolean_option(option_dict,
                                                'autodoc_tree_index_modules',
                                                'AUTODOC_TREE_INDEX_MODULES')
        auto_index = options.get_boolean_option(option_dict,
                                                'autodoc_index_modules',
                                                'AUTODOC_INDEX_MODULES')
        if not os.getenv('SPHINX_DEBUG'):
            # NOTE(afazekas): These options can be used together,
            # but they do a very similar thing in a different way
            if tree_index:
                self._sphinx_tree()
            if auto_index:
                self.generate_autoindex(
                    set(option_dict.get(
                        "autodoc_exclude_modules",
                        [None, ""])[1].split()))

def run(self):
        option_dict = self.distribution.get_option_dict('pbr')
        if git._git_is_installed():
            git.write_git_changelog(option_dict=option_dict)
            git.generate_authors(option_dict=option_dict)
        tree_index = options.get_boolean_option(option_dict,
                                                'autodoc_tree_index_modules',
                                                'AUTODOC_TREE_INDEX_MODULES')
        auto_index = options.get_boolean_option(option_dict,
                                                'autodoc_index_modules',
                                                'AUTODOC_INDEX_MODULES')
        if not os.getenv('SPHINX_DEBUG'):
            # NOTE(afazekas): These options can be used together,
            # but they do a very similar thing in a different way
            if tree_index:
                self._sphinx_tree()
            if auto_index:
                self.generate_autoindex(
                    set(option_dict.get(
                        "autodoc_exclude_modules",
                        [None, ""])[1].split()))