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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 _load_raw_data(self, resource_name):
 """Extract raw data from resource :param resource_name: """

        # Instantiating the resource again as a simple `Resource` ensures that
        # ``data`` will be returned as bytes.
        upcast_resource = datapackage.Resource(
            self.__resources[resource_name].descriptor,
            default_base_path=self.__base_path)
        return upcast_resource.data