message: [Python] String(s) and bytes are two different entities in 3.7.
  So, we need an explicit call to decode() here to let it work with
  both interpreters. Fixes TestXMMRegisters on 3.7.
diff: @@ -803,7 +803,7 @@ def skipUnlessFeature(feature):
  if platform.system() == 'Darwin':
  try:
  DEVNULL = open(os.devnull, 'w')
  - output = subprocess.check_output(["/usr/sbin/sysctl", feature], stderr=DEVNULL)
  + output = subprocess.check_output(["/usr/sbin/sysctl", feature], stderr=DEVNULL).decode("utf-8")
  # If 'feature: 1' was output, then this feature is available and
  # the test should not be skipped.
  if re.match('%s: 1\s*' % feature, output):
  