docstr: 测试单个张量转换为Jittor
docstr_tok: ["\u6d4b\u8bd5\u5355\u4e2a\u5f20\u91cf\u8f6c\u6362\u4e3aJittor"]
code: def test_tensor_transfer(self):
      """
      测试单个张量转换为Jittor
      """
  
      torch_tensor = torch.rand((3, 4, 5))
      res = torch2jittor(torch_tensor)
      self.check_jittor_var(res, False)
  
      res = torch2jittor(torch_tensor, no_gradient=None)
      self.check_jittor_var(res, False)
  
      res = torch2jittor(torch_tensor, no_gradient=True)
      self.check_jittor_var(res, False)
  
      res = torch2jittor(torch_tensor, no_gradient=False)
      self.check_jittor_var(res, True)
  
imports: import pytest
  from fastNLP.envs.imports import _NEED_IMPORT_JITTOR, _NEED_IMPORT_PADDLE, _NEED_IMPORT_TORCH
  from fastNLP.modules.mix_modules.utils import paddle2torch, torch2paddle, jittor2torch, torch2jittor
label_desc: Use image node_id 3 for calling the TestTorch2Jittor obj's underlying member method code with example usage: obj.test_tensor_transfer() without return types