message: update simple_subunit.py.txt example
diff: @@ -13,10 +13,10 @@ class subunit0(BasicRtlSimModel):
  # ports
  self.io.a = BasicRtlSimProxy(
  sim, self, "a",
  - Bits3t(1, 0), None)
  + Bits3t(1, None), None)
  self.io.b = BasicRtlSimProxy(
  sim, self, "b",
  - Bits3t(1, 0), None)
  + Bits3t(1, None), None)
  # internal signals
  # component instances
  def _init_body(self):
  @@ -45,17 +45,17 @@ class SimpleSubunit(BasicRtlSimModel):
  # ports
  self.io.a = BasicRtlSimProxy(
  sim, self, "a",
  - Bits3t(1, 0), None)
  + Bits3t(1, None), None)
  self.io.b = BasicRtlSimProxy(
  sim, self, "b",
  - Bits3t(1, 0), None)
  + Bits3t(1, None), None)
  # internal signals
  self.io.sig_subunit0_a = BasicRtlSimProxy(
  sim, self, "sig_subunit0_a",
  - Bits3t(1, 0), None)
  + Bits3t(1, None), None)
  self.io.sig_subunit0_b = BasicRtlSimProxy(
  sim, self, "sig_subunit0_b",
  - Bits3t(1, 0), None)
  + Bits3t(1, None), None)
  # component instances
  self.subunit0_inst = subunit0(sim, "subunit0_inst")
  def _init_body(self):
  