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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 _cost_method(self, *args, **kwargs):
 """Calculate low-rank component of the cost This method returns the nuclear norm error of the deconvolved data in matrix form Returns ------- float low-rank cost component """


        cost_val = self.thresh * nuclear_norm(cube2matrix(args[0]))

        if 'verbose' in kwargs and kwargs['verbose']:
            print(' - NUCLEAR NORM (X):', cost_val)

        return cost_val