code: def test_silhouette_reduce(sparse_container):
      """Check for non-CSR input to private method `_silhouette_reduce`."""
      X = np.array(
          [[0.2, 0.1, 0.1, 0.2, 0.1, 1.6, 0.2, 0.1]], dtype=np.float32
      ).T
      pdist_dense = pairwise_distances(X)
      pdist_sparse = sparse_container(pdist_dense)
      y = [0, 0, 0, 0, 1, 1, 1, 1]
      label_freqs = np.bincount(y)
      with pytest.raises(
          TypeError,
          match="Expected CSR matrix. Please pass sparse matrix in CSR format.",
      ):
          _silhouette_reduce(
              pdist_sparse, start=0, labels=y, label_freqs=label_freqs
          )
  
imports: import warnings
  import numpy
  import pytest
  from numpy.testing import assert_allclose
  from scipy.sparse import issparse
  from sklearn import datasets
  from sklearn.metrics import pairwise_distances
  from sklearn.metrics.cluster import calinski_harabasz_score, davies_bouldin_score, silhouette_samples, silhouette_score
  from sklearn.metrics.cluster._unsupervised import _silhouette_reduce
  from sklearn.utils._testing import assert_array_equal
  from sklearn.utils.fixes import CSC_CONTAINERS, CSR_CONTAINERS, DOK_CONTAINERS, LIL_CONTAINERS
label_desc: Use image node_id 10 for calling a global function with example usage: test_silhouette_reduce(sparse_container) without return types