code: def test_classifier_numerical_variables(df_regression):
      X, y = df_regression
  
      tr = TargetMeanRegressor(variables="num_var_A", bins=2)
      tr.fit(X, y)
  
      pred = tr.predict(X)
  
      exp_pred = np.array(
          [
              0.5,
              0.5,
              0.5,
              0.5,
              0.5,
              0.5,
              0.5,
              0.5,
              0.5,
              0.5,
              2.5,
              2.5,
              2.5,
              2.5,
              2.5,
              2.5,
              2.5,
              2.5,
              2.5,
              2.5,
          ]
      )
  
      assert np.array_equal(pred, exp_pred)
  
      tr = TargetMeanRegressor(variables="num_var_B", bins=2)
      tr.fit(X, y)
  
      pred = tr.predict(X)
  
      exp_pred = np.array(
          [
              0.7,
              0.7,
              0.7,
              0.7,
              0.7,
              0.7,
              0.7,
              0.7,
              2.3,
              2.3,
              0.7,
              0.7,
              2.3,
              2.3,
              2.3,
              2.3,
              2.3,
              2.3,
              2.3,
              2.3,
          ]
      )
  
      np.array_equal(pred, exp_pred)
  
      tr = TargetMeanRegressor(
          variables=["num_var_A", "num_var_B"], bins=2
      )
      tr.fit(X, y)
  
      pred = tr.predict(X)
  
      exp_pred = np.array(
          [
              0.6,
              0.6,
              0.6,
              0.6,
              0.6,
              0.6,
              0.6,
              0.6,
              1.4,
              1.4,
              1.6,
              1.6,
              2.4,
              2.4,
              2.4,
              2.4,
              2.4,
              2.4,
              2.4,
              2.4,
          ]
      )
  
      assert np.array_equal(pred, exp_pred)
  
imports: import numpy
  from feature_engine._prediction.target_mean_regressor import TargetMeanRegressor
label_desc: Use image node_id 2 for calling a global function with example usage: test_classifier_numerical_variables(df_regression) without return types