message: Fix python not_() operator
diff: @@ -135,7 +135,7 @@ def not_(a0):
  if a0.IsFloat:
  raise Exception("not(): requires an integral or mask operand!")
  ar, sr = _check1(a0)
  - if type(a0.Value) is bool:
  + if a0.Value is bool:
  for i in range(sr):
  ar[i] = not a0[i]
  else:
  