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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 density(self, R, Rs, rho0, r_core):
 """ three dimenstional truncated NFW profile :param R: radius of interest :type R: float/numpy array :param Rs: scale radius :type Rs: float :param rho0: density normalization (central core density) :type rho0: float :return: rho(R) density """


        M0 = 4*np.pi*rho0 * Rs ** 3
        return (M0/4/np.pi) * ((r_core + R)*(R + Rs)**2) ** -1