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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 keys(self, latest=False):
 """ Return a list of the keys in this directory. Parameters latest : bool, optional (default=False) If True then return a list of keys with unique names where only the key with the highest cycle number is included where multiple keys exist with the same name. Returns ------- keys : list List of keys """

        if latest:
            keys = {}
            for key in self.keys():
                name = key.GetName()
                if name in keys:
                    if key.GetCycle() > keys[name].GetCycle():
                        keys[name] = key
                else:
                    keys[name] = key
            return keys.values()
        return [asrootpy(key) for key in self.GetListOfKeys()]