code: def test_abline_ab(self, close_figures):
      mod = self.mod
      intercept, slope = mod.params
      fig = abline_plot(intercept=intercept, slope=slope)
      close_or_save(pdf, fig)
  
imports: import numpy
  from numpy.testing import assert_array_less, assert_equal, assert_raises
  from pandas import DataFrame, Series
  import pytest
  import statsmodels.api
  from statsmodels.graphics.regressionplots import abline_plot, add_lowess, influence_plot, plot_added_variable, plot_ccpr, plot_ccpr_grid, plot_ceres_residuals, plot_fit, plot_leverage_resid2, plot_partial_residuals, plot_partregress_grid, plot_regress_exog
label_desc: Use image node_id 4 for calling the TestABLine obj's underlying member method code with example usage: obj.test_abline_ab(close_figures) without return types