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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 spline_factors(u):
    '''u is np.array'''

    X = np.array([(1.-u)**3 , 4-(6.*(u**2))+(3.*(u**3)) , 1.+(3.*u)+(3.*(u**2))-(3.*(u**3)) , u**3]) * (1./6)
    
    return X