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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 configure_discovery(graph):
 """ Build a singleton endpoint that provides a link to all search endpoints. """

    ns = Namespace(
        subject=graph.config.discovery_convention.name,
    )
    convention = DiscoveryConvention(graph)
    convention.configure(ns, discover=tuple())
    return ns.subject