def xview(self, index=None):
        """If index is not given a tuple containing two fractions is returned,
        each fraction is between 0 and 1. Together they describe the
        horizontal span that is visible in the window.

        If index is given the view in the window is adjusted so that the
        column given by index is displayed at the left edge of the window."""
        res = self.tk.call(self._w, 'xview', index)
        if index is None:
            return self._getdoubles(res)
dataset/ETHPy150Open Arelle/Arelle/arelle/TkTableWrapper.py/Table.xview/original