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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 _update_separator(self, offset):
 """ Compute colorbar offset and update separator line if map is non-zero. """

        offset_line = self.handles['offset_line']
        if offset == 0:
            offset_line.set_visible(False)
        else:
            offset_line.set_visible(True)
            if self.invert_axes:
                offset_line.set_xdata(offset)
            else:
                offset_line.set_ydata(offset)