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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 subliminal(ctx, addic7ed, legendastv, opensubtitles, subscenter, cache_dir, debug):
 """Subtitles, faster than your thoughts."""

    # create cache directory
    try:
        os.makedirs(cache_dir)
    except OSError:
        if not os.path.isdir(cache_dir):
            raise

    # configure cache
    region.configure('dogpile.cache.dbm', expiration_time=timedelta(days=30),
                     arguments={'filename': os.path.join(cache_dir, cache_file), 'lock_factory': MutexLock})

    # configure logging
    if debug:
        handler = logging.StreamHandler()
        handler.setFormatter(logging.Formatter(logging.BASIC_FORMAT))
        logging.getLogger('subliminal').addHandler(handler)
        logging.getLogger('subliminal').setLevel(logging.DEBUG)

    # provider configs
    ctx.obj = {'provider_configs': {}}
    if addic7ed:
        ctx.obj['provider_configs']['addic7ed'] = {'username': addic7ed[0], 'password': addic7ed[1]}
    if legendastv:
        ctx.obj['provider_configs']['legendastv'] = {'username': legendastv[0], 'password': legendastv[1]}
    if opensubtitles:
        ctx.obj['provider_configs']['opensubtitles'] = {'username': opensubtitles[0], 'password': opensubtitles[1]}
    if subscenter:
        ctx.obj['provider_configs']['subscenter'] = {'username': subscenter[0], 'password': subscenter[1]}