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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 _opposite_axis_margin(self):
 """ndarray representing margin along the axis opposite of self._axis In the process of calculating p-values for the column significance testing we need both the margin along the primary axis and the percentage margin along the opposite axis. """

        off_axis = 1 - self._axis
        return self._slice.margin(axis=off_axis, include_mr_cat=self._include_mr_cat)