def METHOD_NAME(self):
    lens_model_list = ["SPEP", "SHEAR"]
    lensModel = LensModel(lens_model_list=lens_model_list)
    lensModelExtensions = LensModelExtensions(lensModel=lensModel)
    lensEquationSolver = LensEquationSolver(lensModel=lensModel)
    x_source, y_source = 0.02, 0.01
    kwargs_lens = [
        {
            "theta_E": 1.0,
            "e1": 0.1,
            "e2": 0.1,
            "gamma": 2.0,
            "center_x": 0,
            "center_y": 0,
        },
        {"gamma1": 0.06, "gamma2": -0.03},
    ]
    x_img, y_img = lensEquationSolver.image_position_from_source(
        kwargs_lens=kwargs_lens, sourcePos_x=x_source, sourcePos_y=y_source
    )
    print("image positions are: ", x_img, y_img)
    mag_inf = lensModel.magnification(x_img, y_img, kwargs_lens)
    print("point source magnification: ", mag_inf)
    source_size_arcsec = 0.001
    window_size = 0.1
    grid_number = 100
    print("source size in arcsec: ", source_size_arcsec)
    mag_finite = lensModelExtensions.magnification_finite(
        x_pos=x_img,
        y_pos=y_img,
        kwargs_lens=kwargs_lens,
        source_sigma=source_size_arcsec,
        window_size=window_size,
        grid_number=grid_number,
    )
    flux_ratios = mag_finite[1:] / mag_finite[0]
    flux_ratio_errors = [0.1, 0.1, 0.1]
    flux_ratio_cov = np.diag([0.1, 0.1, 0.1]) ** 2
    self.flux_likelihood = FluxRatioLikelihood(
        lens_model_class=lensModel,
        flux_ratios=flux_ratios,
        flux_ratio_errors=flux_ratio_errors,
        source_type="GAUSSIAN",
        window_size=window_size,
        grid_number=grid_number,
    )
    self.flux_likelihood_inf = FluxRatioLikelihood(
        lens_model_class=lensModel,
        flux_ratios=flux_ratios,
        flux_ratio_errors=flux_ratio_errors,
        source_type="INF",
        window_size=window_size,
        grid_number=grid_number,
    )
    self.flux_likelihood_inf_cov = FluxRatioLikelihood(
        lens_model_class=lensModel,
        flux_ratios=flux_ratios,
        flux_ratio_errors=flux_ratio_cov,
        source_type="INF",
        window_size=window_size,
        grid_number=grid_number,
    )
    self.kwargs_cosmo = {"source_size": source_size_arcsec}
    self.x_img, self.y_img = x_img, y_img
    self.kwargs_lens = kwargs_lens