code: def test_get_radius(self):
      df = pd.DataFrame(
          np.random.randint(0, 100, size=(5, 4)), columns=list("ABCD")
      ).values
      t = _get_radius(df, n_neighbors=3)
      assert t > 0
  
file_path: shapash/tests/unit_tests/utils/test_explanation_metrics.py
imports: import unittest
  import numpy
  import pandas
  from sklearn.linear_model import LinearRegression
  from shapash.utils.explanation_metrics import _df_to_array, _compute_distance, _compute_similarities, _get_radius, find_neighbors, shap_neighbors, get_min_nb_features, get_distance
label_desc: Use image node_id 4 for calling the TestExplanationMetrics obj's underlying member method code with example usage: obj.test_get_radius() without return types