code: def test_exceptions(self):
      im = torch.zeros((1, 2, 3))
      im_nodim = MetaTensor(im, meta={"original_channel_dim": None})
  
      with self.assertRaises(ValueError):  # no meta
          EnsureChannelFirstd("img", channel_dim=None)({"img": im})
      with self.assertRaises(ValueError):  # no meta channel
          EnsureChannelFirstd("img", channel_dim=None)(
              {"img": im_nodim}
          )
  
      with self.assertWarns(Warning):
          EnsureChannelFirstd(
              "img", strict_check=False, channel_dim=None
          )({"img": im})
  
      with self.assertWarns(Warning):
          EnsureChannelFirstd(
              "img", strict_check=False, channel_dim=None
          )({"img": im_nodim})
  
file_path: MONAI/tests/test_ensure_channel_firstd.py
imports: from __future__ import annotations
  import os
  import tempfile
  import unittest
  import nibabel
  import numpy
  import torch
  from parameterized import parameterized
  from PIL import Image
  from monai.data.meta_tensor import MetaTensor
  from monai.transforms import EnsureChannelFirstd, LoadImaged
label_desc: Use image node_id 3 for calling the TestEnsureChannelFirstd obj's underlying member method code with example usage: obj.test_exceptions() without return types