code: def hexStr(s):
      h = string.hexdigits
      r = ""
      for c in s:
          i = byteord(c)
          r = r + h[(i >> 4) & 0xF] + h[i & 0xF]
      return r
  
imports: from fontTools.misc.textTools import byteord, strjoin, tobytes, tostr
  import sys
  import os
  import string
label_desc: Use image node_id 4 for calling a global function with example usage: hexStr(s) and returns: r