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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_sources(self, resources):
 """ Filter resources based on which have this reference """


        rtype = self.rtype  # E.g. category
        label = self.props.label  # E.g. category1
        result = [
            resource
            for resource in resources.values()
            if is_reference_target(resource, rtype, label)
        ]
        return result