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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 compute_edge_reduction(self) -> float: """Compute the edge reduction. Costly computation"""

        nb_init_edge = self.init_edge_number()
        nb_poweredge = self.edge_number()
        return (nb_init_edge - nb_poweredge) / (nb_init_edge)