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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 _premium(fn):
 """Premium decorator for APIs that require premium access level."""

        @_functools.wraps(fn)
        def _fn(self, *args, **kwargs):
            if self._lite:
                raise RuntimeError('Premium API not available in lite access.')
            return fn(self, *args, **kwargs)
        return _fn