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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 read_config(source, current_name):
 """Read the Sphinx config for one version. :raise HandledError: If sphinx-build fails. Will be logged before raising. :param str source: Source directory to pass to sphinx-build. :param str current_name: The ref name of the current version being built. :return: Specific Sphinx config values. :rtype: dict """

    log = logging.getLogger(__name__)
    queue = multiprocessing.Queue()
    config = Config.from_context()

    with TempDir() as temp_dir:
        argv = ('sphinx-build', source, temp_dir)
        log.debug('Running sphinx-build for config values with args: %s', str(argv))
        child = multiprocessing.Process(target=_read_config, args=(argv, config, current_name, queue))
        child.start()
        child.join()  # Block.
        if child.exitcode != 0:
            log.error('sphinx-build failed for branch/tag while reading config: %s', current_name)
            raise HandledError

    config = queue.get()
    return config