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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 iter_units_for_relation_name(relation_name):
 """Iterate through all units in a relation Generator that iterates through all the units in a relation and yields a named tuple with rid and unit field names. Usage: data = [(u.rid, u.unit) for u in iter_units_for_relation_name(relation_name)] :param relation_name: string relation name :yield: Named Tuple with rid and unit field names """

    RelatedUnit = namedtuple('RelatedUnit', 'rid, unit')
    for rid in relation_ids(relation_name):
        for unit in related_units(rid):
            yield RelatedUnit(rid, unit)