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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 rtc_as_set(self):
 """Returns current RTC AS configured for current neighbors. """

        rtc_as_set = set()
        for neigh in self._neighbors.values():
            rtc_as_set.add(neigh.rtc_as)
        return rtc_as_set