code: def chunk_cHRM(self, pos, length):
      # chromaticity, 8 unsigned ints, actual value is scaled by 100,000
      # WP x,y, Red x,y, Green x,y Blue x,y
  
      s = ImageFile._safe_read(self.fp, length)
      raw_vals = struct.unpack(">%dI" % (len(s) // 4), s)
      self.im_info["chromaticity"] = tuple(
          elt / 100000.0 for elt in raw_vals
      )
      return s
  
imports: import logging
  import re
  import struct
  import zlib
  from .None import Image, ImageFile, ImagePalette
  from ._binary import i8, i16be, i32be, o16be, o32be
  from ._util import py3
label_desc: Use image node_id 10 for calling the PngStream obj's underlying member method code with example usage: obj.chunk_cHRM(pos, length) and returns: s