class_docstr: misc unittest
docstr: per device batch size unittest
code: def test_per_device_batch_size(self):
      """per device batch size unittest"""
      batch_size, ngpus = 32, 2
      batch_per_dev = misc.per_device_batch_size(batch_size, ngpus)
      self.assertEqual(batch_per_dev, 16)
  
      batch_size, ngpus = 32, 1
      batch_per_dev = misc.per_device_batch_size(batch_size, ngpus)
      self.assertEqual(batch_per_dev, 32)
  
      with self.assertRaises(ValueError):
          batch_size, ngpus = 32, 3
          batch_per_dev = misc.per_device_batch_size(batch_size, ngpus)
  
file_path: delta/delta/utils/misc_test.py
imports: import numpy
  import delta.compat
  from delta.utils import misc
label_desc: Use image node_id 6 for calling the MiscTest obj's underlying member method code with example usage: obj.test_per_device_batch_size() without return types