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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 noise_covariance(fit, dof=2, **kw):
 """ Covariance taking into account the 'noise covariance' of the data. This is technically more realistic for continuously sampled data. From Faber, 1993 """

    ev = fit.eigenvalues

    measurement_noise = ev[-1]/(fit.n-dof)
    return 4*ev*measurement_noise