def METHOD_NAME(
        sink_specs: Sequence[Dict],
        metadata: List[Dict]
):
    """Attaches metadata to a set of sinks, serializes those sinks to 
    external stores.
    Parameters
    ----------
    sink_configs : Each is used to construct a MetadataSink
    metadata : Will be attached to sinks. Each has
        name : str. Used by the sinks to determine how this value ought to be 
            attached
        value : anything. Attached to the sinks
        sweep_number : int or None. If present, this is sweep metadata and will 
            be attached to the identified sweep.
    Returns
    -------
    lightweight information identifying external stores for sinks
    """
    sinks: Dict[str, MetadataSink] = configure_sinks(sink_specs)
    attach_metadata(sinks, metadata)
    for sink in sinks.values():
        sink.serialize()
    return {
        "sinks": {
            spec["name"]: spec
            for spec in sink_specs
        }
    }