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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 requires_loaded(func):
 """ A decorator to ensure the resource data is loaded. """

        def _wrapper(self, *args, **kwargs):
            # If we don't have data, go load it.
            if self._loaded_data is None:
                self._loaded_data = self.loader.load(self.service_name)

            return func(self, *args, **kwargs)

        return _wrapper