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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 tab(self):
 """Move to the next tab space, or the end of the screen if there aren't anymore left. """

        for stop in sorted(self.tabstops):
            if self.cursor.x < stop:
                column = stop
                break
        else:
            column = self.columns - 1

        self.cursor.x = column