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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 setup_concept_scheme(rdf, defaultcs):
 """Make sure all concepts have an inScheme property, using the given default concept scheme if necessary."""

    for conc in rdf.subjects(RDF.type, SKOS.Concept):
        # check concept scheme
        cs = rdf.value(conc, SKOS.inScheme, None, any=True)
        if cs is None:  # need to set inScheme
            rdf.add((conc, SKOS.inScheme, defaultcs))