class_docstr: CMVN unittest Class
docstr: test creat_cmvn_statics 
docstr_tok: ["test","creat_cmvn_statics"]
code: def testCreateCmvnStatis(self):  # pylint: disable=invalid-name
      """test creat_cmvn_statics"""
      feat_size = 40
      delta_deltas = True
  
      sums, square, count = utils.create_cmvn_statis(
          feat_size, delta_deltas
      )
  
      self.assertAllEqual(sums.shape, [1, feat_size, 3])
      self.assertAllEqual(square.shape, [1, feat_size, 3])
      self.assertAllEqual(count, 0)
  
      delta_deltas = False
      sums, square, count = utils.create_cmvn_statis(
          feat_size, delta_deltas
      )
      self.assertAllEqual(sums.shape, [1, feat_size, 1])
      self.assertAllEqual(square.shape, [1, feat_size, 1])
      self.assertAllEqual(count, 0)
  
file_path: delta/delta/utils/cmvn_test.py
imports: import os
  import numpy
  import delta.compat
  from delta import utils
label_desc: Use image node_id 3 for calling the CmvnTest obj's underlying member method code with example usage: obj.testCreateCmvnStatis() without return types