code: def _missing_warn():
      """Print a warning when called."""
      warnings.warn(
          "One of the clusters is empty. "
          "Re-run kmeans with a different initialization.",
          stacklevel=3,
      )
  
imports: import warnings
  import numpy
  from collections import deque
  from scipy._lib._array_api import as_xparray, array_namespace, size, atleast_nd, copy, cov
  from scipy._lib._util import check_random_state, rng_integers
  from scipy.spatial.distance import cdist
  from .None import _vq
label_desc: Use image node_id 9 for calling a global function with example usage: _missing_warn() without return types