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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 get_rml(self, rml_name):
 """ returns the rml mapping RdfDataset rml_name(str):
 Name of the rml mapping to retrieve """


        try:
            return getattr(self, rml_name)
        except AttributeError:
            return self.load_rml(rml_name)