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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 _mappingGetValueSet(mapping, keys):
 """Return a combined set of values from the mapping. :param mapping: dict, for each key contains a set of entries returns a set of combined entries """

    setUnion = set()
    for k in keys:
        setUnion = setUnion.union(mapping[k])
    return setUnion