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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 runner(coro):
 """Function execution decorator."""


    @wraps(coro)
    def inner(self, *args, **kwargs):
        if self.mode == 'async':
            return coro(self, *args, **kwargs)
        return self._loop.run_until_complete(coro(self, *args, **kwargs))

    return inner