code: def pct_in_window(dcm: DcmDataset, w, l):
      "% of pixels in the window `(w,l)`"
      px = dcm.scaled_px
      return (
          ((px > l - w // 2) & (px < l + w // 2)).float().mean().item()
      )
  
imports: from __future__ import annotations
  from ..basics import *
  from ..vision.all import *
  from ..data.transforms import *
  import pydicom, kornia, skimage
  from pydicom.dataset import Dataset
  from pydicom.tag import BaseTag
  from pydicom.multival import MultiValue
  from PIL import Image
label_desc: Use image node_id 15 for calling a global function with example usage: pct_in_window(dcm, w, l) and returns: unknown