code: def preprocess(self, cfg, imgs_path, batch_size, batch_id):
      for img in imgs_path[batch_id : batch_id + batch_size]:
          im_list = []
          imgs = np.load(img)
          imgs = imgs[:, np.newaxis, :, :]
          for i in range(imgs.shape[0]):
              im = imgs[i]
              im = cfg.transforms(im)[0]
              im_list.append(im)
          img = np.concatenate(im_list)
      return img
  
imports: import numpy
  from medicalseg.cvlibs import manager
  from medicalseg.inference_helpers import InferenceHelper
label_desc: Use image node_id 1 for calling the InferenceHelper2D obj's underlying member method code with example usage: obj.preprocess(cfg, imgs_path, batch_size, batch_id) and returns: img