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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 row(self):
 """ Returns the periodic table row of the element. """

        z = self.Z
        total = 0
        if 57 <= z <= 71:
            return 8
        elif 89 <= z <= 103:
            return 9

        for i in range(len(_pt_row_sizes)):
            total += _pt_row_sizes[i]
            if total >= z:
                return i + 1
        return 8