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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 generate(self):
 """ Add provenance info to the context graph. """

        t = (self.context.identifier, RDF.type, META.Provenance)
        if t not in self.context.graph:
            self.context.graph.add(t)
        for name, value in self.data.items():
            pat = (self.context.identifier, META[name], None)
            if pat in self.context.graph:
                self.context.graph.remove(pat)
            self.context.graph.add((pat[0], META[name], Literal(value)))