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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):
 """ three dimenstional NFW profile :param R: radius of interest :type R: float/numpy array :param Rs: scale radius :type Rs: float :param rho0: density normalization (characteristic density) :type rho0: float :return: rho(R) density """

        return rho0/(R/Rs*(1+R/Rs)**2)