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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 constant_coefficients(d, timelines, constant=True, independent=0):
 """ Proportional hazards model. d: the dimension of the dataset timelines: the observational times constant: True for constant coefficients independent: the number of coffients to set to 0 (covariate is ind of survival), or a list of covariates to make indepent. returns a matrix (t,d+1) of coefficients """

    return time_varying_coefficients(d, timelines, constant, independent=independent, randgen=random.normal)