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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 list_archivers(config):
 """ List the names of archivers with data. :param config: The configuration :type config: :class:`wily.config.WilyConfig` :return: A list of archiver names :rtype: ``list`` of ``str`` """

    root = pathlib.Path(config.cache_path)
    result = []
    for name in ALL_ARCHIVERS.keys():
        if (root / name).exists():
            result.append(name)
    return result