import re


def check_log_id(log_id):
    """
    Check log_id syntax
    :param log_id: string
    :return SRE_Match object

    >>> check_log_id("5ab13d4673c5787c54a75e1d") is not None
    True

    >>> check_log_id("/etc/test") is not None
    False
    """
    return re.match("^[a-f0-9]{24}$", log_id)