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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 Series with the last n values. Parameters n : int Number of values. Returns ------- Series Series containing the last n values. Examples -------- <BLANKLINE> --- -- 1 1 2 2 """

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

        return _series_tail(self, self.index.tail(n), length, n)