code: def test_mixed_types():
      a = ["a", "b"]
      b = [(1, 2, 3)]
      assert _product(a, b) == [("a", (1, 2, 3)), ("b", (1, 2, 3))]
  
imports: import pytest
  import numpy
  from sklearn_evaluation.util import _can_iterate, is_column_vector, is_row_vector, _group_by, _product, _mapping_to_tuple_pairs, map_parameters_in_fn_call
label_desc: Use image node_id 26 for calling a global function with example usage: test_mixed_types() without return types