code: def _covar_mstep_spherical(*args):
      """Perform the covariance M step for spherical cases."""
      cv = _covar_mstep_diag(*args)
      return np.tile(cv.mean(axis=1)[:, np.newaxis], (1, cv.shape[1]))
  
imports: import numpy
  from scipy import linalg
  from time import time
  from ..base import BaseEstimator
  from ..utils import check_random_state, check_array, deprecated
  from ..utils.extmath import logsumexp
  from ..utils.validation import check_is_fitted
  from ..None import cluster
  from sklearn.externals.six.moves import zip
label_desc: Use image node_id 10 for calling a global function with example usage: _covar_mstep_spherical() and returns: np