code: def test_to_coo_midx_categorical(self):
      # GH#50996
      sp_sparse = pytest.importorskip("scipy.sparse")
  
      midx = pd.MultiIndex.from_arrays(
          [
              pd.CategoricalIndex(list("ab"), name="x"),
              pd.CategoricalIndex([0, 1], name="y"),
          ]
      )
  
      ser = pd.Series(1, index=midx, dtype="Sparse[int]")
      result = ser.sparse.to_coo(row_levels=["x"], column_levels=["y"])[
          0
      ]
      expected = sp_sparse.coo_matrix(
          (np.array([1, 1]), (np.array([0, 1]), np.array([0, 1]))),
          shape=(2, 2),
      )
      assert (result != expected).nnz == 0
  
imports: import string
  import numpy
  import pytest
  import pandas
  from pandas import SparseDtype
  import pandas._testing
  from pandas.core.arrays.sparse import SparseArray
label_desc: Use image node_id 7 for calling the TestFrameAccessor obj's underlying member method code with example usage: obj.test_to_coo_midx_categorical() without return types