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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 _check_has_primary(sds):
 """Current topology type is ReplicaSetWithPrimary. Is primary still known? Pass in a dict of ServerDescriptions. Returns new topology type. """

    for s in sds.values():
        if s.server_type == SERVER_TYPE.RSPrimary:
            return TOPOLOGY_TYPE.ReplicaSetWithPrimary
    else:
        return TOPOLOGY_TYPE.ReplicaSetNoPrimary