code: def test_split_src_to_prevent_padding_target_prefix_is_none_when_equal_size(  # noqa: E501
      self,
  ):
      src = torch.randint(0, 10, (6, 5, 1))
      src_len = 5 * torch.ones(5, dtype=torch.int)
      (
          src,
          src_len,
          target_prefix,
      ) = GeneratorLM.split_src_to_prevent_padding(src, src_len)
      self.assertIsNone(target_prefix)
  
imports: import unittest
  from onmt.translate import GeneratorLM
  import torch
label_desc: Use image node_id 1 for calling the TestGeneratorLM obj's underlying member method code with example usage: obj.test_split_src_to_prevent_padding_target_prefix_is_none_when_equal_size() without return types