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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 ruler_line(self, widths, linetype='-'):
 """Generates a ruler line for separating rows from each other"""

        cells = []
        for w in widths:
            cells.append(linetype * (w+2))
        return '+' + '+'.join(cells) + '+'