code: def test_common_three_tokens(self):
      assert fn.commonThreeTokens("d on 456 ld") == {
          "d on 456",
          "on 456 ld",
      }
      assert fn.commonThreeTokens("donald 1992") == frozenset()
      assert fn.commonThreeTokens("g00fy  ") == frozenset()
      assert fn.commonThreeTokens(" c1p   c10p  c100p") == {
          "c1p c10p c100p"
      }
  
imports: import unittest
  from dedupe import predicate_functions
  from dedupe.cpredicates import ngrams
label_desc: Use image node_id 12 for calling the TestPredicateFunctions obj's underlying member method code with example usage: obj.test_common_three_tokens() without return types