code: def _add_blur(tens, x, y, hw, fog_coeff) -> Tensor:
      tens = to_tensor(tens, override_checks=True)
  
      overlay = tens.clone()
      output = tens.clone()
  
      alpha = 0.08 * fog_coeff
      rad = hw // 2
      point = (x + hw // 2, y + hw // 2)
      cv.circle(overlay, point, int(rad), (255, 255, 255), -1)
      cv.addWeighted(overlay, alpha, output, 1 - alpha, 0, output)
  
      return to_tensor(output, override_checks=True)
  
imports: import cv2
  import random
  import math
  import numpy
  from ..coreten import Tensor, to_tensor
  from ..annotations import Tuple, Union
  from ..color import to_hls, to_rgb, to_bgr, to_hsv, to_gray, to_lab
label_desc: Use image node_id 14 for calling a global function with example usage: _add_blur(tens, x, y, hw, fog_coeff) and returns: to_tensor