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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 add_rows(self, rows, header=True):
 """Add several rows in the rows stack - The 'rows' argument can be either an iterator returning arrays, or a by-dimensional array - 'header' specifies if the first row should be used as the header of the table """


        # nb: don't use 'iter' on by-dimensional arrays, to get a
        #     usable code for python 2.1
        if header:
            if hasattr(rows, '__iter__') and hasattr(rows, 'next'):
                self.header(rows.next())
            else:
                self.header(rows[0])
                rows = rows[1:]
        for row in rows:
            self.add_row(row)
        return self