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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 swaplevel(self, i=-2, j=-1, axis=0):
 """ Swap levels i and j in a MultiIndex on a particular axis Parameters i, j : int, str (can be mixed) Level of index to be swapped. Can pass level name as string. Returns ------- swapped : same type as caller (new object) .. versionchanged:: 0.18.1 The indexes ``i`` and ``j`` are now optional, and default to the two innermost levels of the index. """

        axis = self._get_axis_number(axis)
        result = self.copy()
        labels = result._data.axes[axis]
        result._data.set_axis(axis, labels.swaplevel(i, j))
        return result