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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 hup_hook(signal_or_callable=signal.SIGTERM, verbose=False):
 """ Register a signal handler for `signal.SIGHUP` that checks for modified files and only acts if at least one modified file is found. @type signal_or_callable: str, int or callable @param signal_or_callable: You can pass either a signal or a callable. The signal can be specified by name or number. If specifying by name, the 'SIG' portion is optional. For example, valid values for SIGINT include 'INT', 'SIGINT' and `signal.SIGINT`. Alternatively, you can pass a callable that will be called with the list of changed files. So the call signature should be `func(list)`. The return value of the callable is ignored. @type verbose: bool or callable @param verbose: Defaults to False. True indicates that a message should be printed. You can also pass a callable such as log.info. """


    #noinspection PyUnusedLocal
    def handle_hup(signum, frame):
        changed = modified()
        if changed:
            if callable(signal_or_callable):
                func = signal_or_callable
                args = (changed,)
                op = 'Calling'
                try:
                    name = signal_or_callable.__name__
                except Exception:
                    name = str(signal_or_callable)
            else:
                if isinstance(signal_or_callable, int):
                    name = str(signal_or_callable)
                    signum = signal_or_callable
                    if verbose:
                        for item in dir(signal):
                            if item.startswith('SIG') and getattr(signal, item) == signal_or_callable:
                                name = item
                                break
                else:
                    name = signal_or_callable if signal_or_callable.startswith('SIG') else 'SIG' + signal_or_callable
                    signum = getattr(signal, name)
                func = os.kill
                args = (os.getpid(), signum)
                op = 'Sending'
            if verbose:
                more = ' and {0} other files'.format(len(changed)) if len(changed) > 1 else ''
                message = '{0} {1} because {2}{3} changed'.format(op, name, changed[0], more)
                if callable(verbose):
                    #noinspection PyCallingNonCallable
                    verbose(message)
                else:
                    print(message)
            func(*args)

    files()
    signal.signal(signal.SIGHUP, handle_hup)
    signal.siginterrupt(signal.SIGHUP, False)