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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 combine_focus_with_prev(self):
 """Combine the focus edit widget with the one above."""


        above, ignore = self.get_prev(self.focus)
        if above is None:
            # already at the top
            return

        focus = self.lines[self.focus]
        above.set_edit_pos(len(above.edit_text))
        above.set_edit_text(above.edit_text + focus.edit_text)
        del self.lines[self.focus]
        self.focus -= 1