class_docstr: Add bottom-right padding to a raw image or annotation image.
  Args:
      target_size (list|tuple): The target size after padding.
      im_padding_value (list, optional): The padding value of raw image.
          Default: [127.5, 127.5, 127.5].
      label_padding_value (int, optional): The padding value of annotation image. Default: 255.
  Raises:
      TypeError: When target_size is neither list nor tuple.
      ValueError: When the length of target_size is not 2.
code: def __init__(
      self,
      target_size: Union[List[int], Tuple[int], int],
      im_padding_value: Union[List[int], Tuple[int], int] = (
          128,
          128,
          128,
      ),
      label_padding_value: int = 255,
  ):
      if isinstance(target_size, list) or isinstance(
          target_size, tuple
      ):
          if len(target_size) != 2:
              raise ValueError(
                  "`target_size` should include 2 elements, but it is {}".format(
                      target_size
                  )
              )
      else:
          raise TypeError(
              "Type of target_size is invalid. It should be list or tuple, now is {}".format(
                  type(target_size)
              )
          )
      self.target_size = target_size
      self.im_padding_value = im_padding_value
      self.label_padding_value = label_padding_value
  
imports: import os
  import random
  from typing import Callable, Union, List, Tuple
  import cv2
  import numpy
  from PIL import Image
  import paddlehub.vision.functional
label_desc: Use image node_id 1 to create a new Padding object  with example: obj = Padding(target_size, im_padding_value, label_padding_value)