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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 setup(app):
 """ Install the plugin. Arguments: app (sphinx.application.Sphinx):
 the Sphinx application context """


    app.add_config_value("cache_path", "_cache", "")

    try:
        os.makedirs(app.config.cache_path)
    except OSError as error:
        if error.errno != errno.EEXIST:
            raise

    path = os.path.join(app.config.cache_path, "spec.html")
    spec = fetch_or_load(path)
    app.add_role("validator", docutils_sucks(spec))