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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 grid_complexity(self):
 """Grid complexity of this multigrid hierarchy. Defined as: Number of unknowns on all levels / Number of unknowns on the finest level """

        return sum([level.A.shape[0] for level in self.levels]) /\
            float(self.levels[0].A.shape[0])