code: def test_comparator(self):
      deduper = dedupe.Dedupe(
          [
              {
                  "field": "type",
                  "type": "Categorical",
                  "categories": ["a", "b", "c"],
              }
          ]
      )
  
      record_pairs = (
          ({"type": "a"}, {"type": "b"}),
          ({"type": "a"}, {"type": "c"}),
      )
  
      numpy.testing.assert_array_almost_equal(
          deduper.data_model.distances(record_pairs),
          numpy.array([[0, 0, 1, 0, 0], [0, 0, 0, 1, 0]]),
          3,
      )
  
imports: import random
  import unittest
  import numpy
  import scipy.special
  import dedupe
label_desc: Use image node_id 2 for calling the FieldDistances obj's underlying member method code with example usage: obj.test_comparator() without return types