def test_hist(self): ev = EconVisualizer(self.income, self.countries) ev._hist(self.merged_df, visualize=False) ev = EconVisualizer() ev._hist(self.merged_df, visualize=False) with self.assertRaises(TypeError): ev._hist(10, visualize=False) with self.assertRaises(ValueError): ev._hist(df=self.countries, visualize=False)