human
I wrote the below code

    extensions = set()
    for extension in options.get('extensions', '').split(','):
        extension = extension.strip()
        if (not extension):
            continue
        extensions.add(import_string(extension))
    if (InternationalizationExtension not in extensions):
        extensions.add(InternationalizationExtension)
    def getbool(options, key, default=False):
        (options.get(key, str(default)).lower() in ('1', 'on', 'yes', 'true'))
    environment = Environment(options.get('block_start_string', BLOCK_START_STRING), options.get('block_end_string', BLOCK_END_STRING), options.get('variable_start_string', VARIABLE_START_STRING), options.get('variable_end_string', VARIABLE_END_STRING), options.get('comment_start_string', COMMENT_START_STRING), options.get('comment_end_string', COMMENT_END_STRING), (options.get('line_statement_prefix') or LINE_STATEMENT_PREFIX), (options.get('line_comment_prefix') or LINE_COMMENT_PREFIX), getbool(options, 'trim_blocks', TRIM_BLOCKS), NEWLINE_SEQUENCE, frozenset(extensions), cache_size=0, auto_reload=False)
    if getbool(options, 'newstyle_gettext'):
        environment.newstyle_gettext = True
    source = fileobj.read().decode(options.get('encoding', 'utf-8'))
    try:
        node = environment.parse(source)
        tokens = list(environment.lex(environment.preprocess(source)))
    except TemplateSyntaxError as e:
        return
    finder = _CommentFinder(tokens, comment_tags)
    for (lineno, func, message) in extract_from_ast(node, keywords):
        (yield (lineno, func, message, finder.find_comments(lineno)))

What's a good function header?
assistant
#Here's a good function header.

def babel_extract(fileobj, keywords, comment_tags, options):