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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def babel_extract(fileobj, keywords, comment_tags, options):
 """Babel extraction method for Jinja templates. .. versionchanged:: 2.3 Basic support for translation comments was added. If `comment_tags` is now set to a list of keywords for extraction, the extractor will try to find the best preceeding comment that begins with one of the keywords. For best results, make sure to not have more than one gettext call in one line of code and the matching comment in the same line or the line before. :param fileobj: the file-like object the messages should be extracted from :param keywords: a list of keywords (i.e. function names) that should be recognized as translation functions :param comment_tags: a list of translator tags to search for and include in the results. :param options: a dictionary of additional options (optional) :return: an iterator over ``(lineno, funcname, message, comments)`` tuples. (comments will be empty currently) """

    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)

    environment = get_spontaneous_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,
        str(options.get('trim_blocks', TRIM_BLOCKS)).lower() in \
            ('1', 'on', 'yes', 'true'),
        NEWLINE_SEQUENCE, frozenset(extensions),
        # fill with defaults so that environments are shared
        # with other spontaneus environments.  The rest of the
        # arguments are optimizer, undefined, finalize, autoescape,
        # loader, cache size, auto reloading setting and the
        # bytecode cache
        True, Undefined, None, False, None, 0, False, None
    )

    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:
        # skip templates with syntax errors
        return

    finder = _CommentFinder(tokens, comment_tags)
    for lineno, func, message in extract_from_ast(node, keywords):
        yield lineno, func, message, finder.find_comments(lineno)