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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 rosen_nesterov(self, x, rho=100):
 """needs exponential number of steps in a non-increasing f-sequence. See Jarre (2011) "On Nesterov's Smooth Chebyshev-Rosenbrock Function" """

        f = 0.25 * (x[0] - 1)**2
        f += rho * sum((x[1:] - 2 * x[:-1]**2 + 1)**2)
        return f