code: def test_byte_content(self):
      # if we receive byte strings, we return byte strings
      a = [b"hello", b"andr\xe9"]  # iso-8859-1 bytes
      b = [b"hello", b"andr\xc3\xa9"]  # utf-8 bytes
  
      unified = difflib.unified_diff
      context = difflib.context_diff
  
      check = self.check
      check(difflib.diff_bytes(unified, a, a))
      check(difflib.diff_bytes(unified, a, b))
  
      # now with filenames (content and filenames are all bytes!)
      check(difflib.diff_bytes(unified, a, a, b"a", b"a"))
      check(difflib.diff_bytes(unified, a, b, b"a", b"b"))
  
      # and with filenames and dates
      check(
          difflib.diff_bytes(
              unified, a, a, b"a", b"a", b"2005", b"2013"
          )
      )
      check(
          difflib.diff_bytes(
              unified, a, b, b"a", b"b", b"2005", b"2013"
          )
      )
  
      # same all over again, with context diff
      check(difflib.diff_bytes(context, a, a))
      check(difflib.diff_bytes(context, a, b))
      check(difflib.diff_bytes(context, a, a, b"a", b"a"))
      check(difflib.diff_bytes(context, a, b, b"a", b"b"))
      check(
          difflib.diff_bytes(
              context, a, a, b"a", b"a", b"2005", b"2013"
          )
      )
      check(
          difflib.diff_bytes(
              context, a, b, b"a", b"b", b"2005", b"2013"
          )
      )
  
imports: import difflib
  from test.support import findfile
  import unittest
  import doctest
  import sys
label_desc: Use image node_id 2 for calling the TestBytes obj's underlying member method code with example usage: obj.test_byte_content() without return types