def test_combine_concat(self):
    pc = ['a', 'b']
    # [START combine_concat]
    def concat(values, separator=', '):
      return separator.join(values)
    with_commas = pc | df.CombineGlobally(concat)
    with_dashes = pc | df.CombineGlobally(concat, separator='-')
    # [END combine_concat]
    self.assertEqual(1, len(with_commas))
    self.assertTrue(with_commas[0] in {'a, b', 'b, a'})
    self.assertEqual(1, len(with_dashes))
    self.assertTrue(with_dashes[0] in {'a-b', 'b-a'})
dataset/ETHPy150Open GoogleCloudPlatform/DataflowPythonSDK/google/cloud/dataflow/examples/snippets/snippets_test.py/CombineTest.test_combine_concat/original