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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 get_destinations(self, ascii_listing):
 """ returns all line numbers that are used in a jump. """

        self.destinations = set()
        def collect_destinations(matchobj):
            numbers = matchobj.group("no")
            if numbers:
                self.destinations.update(set(
                    [n.strip() for n in numbers.split(",")]
                ))

        for line in self._iter_lines(ascii_listing):
            self.renum_regex.sub(collect_destinations, line)

        return sorted([int(no) for no in self.destinations if no])