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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 clear_data(self):
 """Clear comboboxes and columns."""

        self.tab = None
        self.cols = []
        self._idx = []
        self.x_col = ''
        self.y_col = ''
        self.w.xcombo.clear()
        self.w.ycombo.clear()
        self.w.x_lo.set_text('')
        self.w.x_hi.set_text('')
        self.w.y_lo.set_text('')
        self.w.y_hi.set_text('')