code: def ishex(c):
      """Return true if the byte ordinal 'c' is a hexadecimal digit in ASCII."""
      assert isinstance(c, bytes)
      return b"0" <= c <= b"9" or b"a" <= c <= b"f" or b"A" <= c <= b"F"
  
file_path: catboost/contrib/tools/python3/src/Lib/quopri.py
label_desc: Use image node_id 7 for calling a global function with example usage: ishex(c) and returns: unknown