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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 until_all_children_in_state(self, state, timeout=None):
 """Return a tornado Future; resolves when all clients are in specified state"""

        futures = [r.until_state(state, timeout=timeout)
                   for r in dict.values(self.children)]
        yield tornado.gen.multi(futures, quiet_exceptions=tornado.gen.TimeoutError)