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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_children_from_slice(self, s):
 """ Retrieves list of children within slice """

        if isinstance(s.start, str):
            s = slice(
                self.get_index_from_name(s.start), s.stop, s.step)
        if isinstance(s.stop, str):
            s = slice(
                s.start, self.get_index_from_name(s.stop), s.step)
        return WellSeries(self.get_children_list()[s])