human
Here's a good function header given the following:
I wrote the below code

    global _libc_setpriority
    if (_libc_setpriority is None):
        _libc_setpriority = load_libc_function('setpriority', errcheck=True)
    def _setpriority(nice_priority):
        '\n                                setpriority    for    this    pid\n\n                                :param    nice_priority:    valid    values    are    -19    to    20\n                                '
        try:
            _libc_setpriority(PRIO_PROCESS, os.getpid(), int(nice_priority))
        except (ValueError, OSError):
            print(_('WARNING:    Unable    to    modify    scheduling    priority    of    process.    Keeping    unchanged!    Check    logs    for    more    info.    '))
            logger.exception('Unable    to    modify    nice    priority')
        else:
            logger.debug(('set    nice    priority    to    %s' % nice_priority))
    nice_priority = conf.get('nice_priority')
    if (nice_priority is not None):
        _setpriority(nice_priority)
    global _posix_syscall
    if (_posix_syscall is None):
        _posix_syscall = load_libc_function('syscall', errcheck=True)
    def _ioprio_set(io_class, io_priority):
        '\n                                ioprio_set    for    this    process\n\n                                :param    io_class:    the    I/O    class    component,    can    be\n                                                                                                    IOPRIO_CLASS_RT,    IOPRIO_CLASS_BE,\n                                                                                                    or    IOPRIO_CLASS_IDLE\n                                :param    io_priority:    priority    value    in    the    I/O    class\n                                '
        try:
            io_class = IO_CLASS_ENUM[io_class]
            io_priority = int(io_priority)
            _posix_syscall(NR_ioprio_set(), IOPRIO_WHO_PROCESS, os.getpid(), IOPRIO_PRIO_VALUE(io_class, io_priority))
        except (KeyError, ValueError, OSError):
           ...

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

def modify_priority(conf, logger):