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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 set_row_height(self, row, tab, height):
 """Sets row height"""


        try:
            old_height = self.row_heights.pop((row, tab))

        except KeyError:
            old_height = None

        if height is not None:
            self.row_heights[(row, tab)] = float(height)