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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 set_xlabels(self, label=None, **kwargs):
 """Label the x axis on the bottom row of the grid."""

        if label is None:
            label = label_from_attrs(self.data[self._x_var])
        for ax in self._bottom_axes:
            ax.set_xlabel(label, **kwargs)
        return self