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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 process_log(file_iterator):
 """ Process the extended ProFTPD log. Args: file_iterator (file):
 any file-like iterator for reading the log or stdin (see :func:`_read_stdin`). Yields: ImportRequest: with each import. """

    for line in file_iterator:
        if "," not in line:
            continue

        parsed = _parse_line(line)

        if not parsed["command"].upper() in ["DELE", "DEL"]:
            continue

        # don't react to anything else, than trigger in form of deleted
        # "lock" file
        if os.path.basename(parsed["path"]) != settings.LOCK_FILENAME:
            continue

        # react only to lock file in in home directory
        dir_name = os.path.dirname(parsed["path"])
        if settings.LOCK_ONLY_IN_HOME:
            if dir_name != settings.DATA_PATH + parsed["username"]:
                continue

        # deleted user
        if not os.path.exists(os.path.dirname(parsed["path"])):
            continue

        # old record, which doesn't need to be parsed again
        if os.path.exists(parsed["path"]):
            continue

        logger.info(
            "Request for processing from user '%s'." % parsed["username"]
        )

        yield process_import_request(
            username=parsed["username"],
            path=os.path.dirname(parsed["path"]),
            timestamp=parsed["timestamp"],
            logger_handler=logger
        )