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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 _build(argv, config, versions, current_name, is_root):
 """Build Sphinx docs via multiprocessing for isolation. :param tuple argv: Arguments to pass to Sphinx. :param sphinxcontrib.versioning.lib.Config config: Runtime configuration. :param sphinxcontrib.versioning.versions.Versions versions: Versions class instance. :param str current_name: The ref name of the current version being built. :param bool is_root: Is this build in the web root? """

    # Patch.
    application.Config = ConfigInject
    if config.show_banner:
        EventHandlers.BANNER_GREATEST_TAG = config.banner_greatest_tag
        EventHandlers.BANNER_MAIN_VERSION = config.banner_main_ref
        EventHandlers.BANNER_RECENT_TAG = config.banner_recent_tag
        EventHandlers.SHOW_BANNER = True
    EventHandlers.CURRENT_VERSION = current_name
    EventHandlers.IS_ROOT = is_root
    EventHandlers.VERSIONS = versions
    SC_VERSIONING_VERSIONS[:] = [p for r in versions.remotes for p in sorted(r.items()) if p[0] not in ('sha', 'date')]

    # Update argv.
    if config.verbose > 1:
        argv += ('-v',) * (config.verbose - 1)
    if config.no_colors:
        argv += ('-N',)
    if config.overflow:
        argv += config.overflow

    # Build.
    result = build_main(argv)
    if result != 0:
        raise SphinxError