def METHOD_NAME(self):
    self.SS_316.rho([300])
    self.SS_316.rho(300)
    assert self.SS_316.rho(to_kelvin(20)) == 7930
    assert self.SS_316.rho(to_kelvin(300)) == 7815
    a = self.SS_316.rho([300, 400, 500])
    b = self.SS_316.rho(np.array([300, 400, 500]))
    assert (a - b).all() == 0