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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 clear_data(self):
        '''
        Free memory
        If many trees are grown this is an useful options since it is saving a
        lot of memory '''
        if self.forest.verbose > 1:
            print('clearing up stuff')
        self.S = None
        self.Uy = None
        self.U = None