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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 tail(self, n=5):
 """Return Index with the last n values. Parameters n : int Number of values. Returns ------- Series Index containing the last n values. Examples -------- [1. 2.] """

        if self.empty:
            return self
        else:
            if self._length is not None:
                length = self._length
            else:
                length = self._lazy_len().weld_expr

            # not computing slice here to use with __getitem__ because we'd need to use len which is eager
            return Index(weld_tail(self.weld_expr, length, n),
                         self.dtype,
                         self.name)