Fix type hints

h11/_connection.py

@@ -323,7 +323,7 @@ def _get_io_object(
         else:
             # General case: the io_dict just has the appropriate reader/writer
             # for this state
-            return io_dict.get((role, state))  # type: ignore
+            return io_dict.get((role, state))  # type: ignore[return-value]
 
     # This must be called after any action that might have caused
     # self._cstate.states to change.

h11/_readers.py

@@ -227,7 +227,7 @@ def expect_nothing(buf: ReceiveBuffer) -> None:
 
 
 ReadersType = Dict[
-    Union[Sentinel, Tuple[Sentinel, Sentinel]],
+    Union[Type[Sentinel], Tuple[Type[Sentinel], Type[Sentinel]]],
     Union[Callable[..., Any], Dict[str, Callable[..., Any]]],
 ]
 

h11/_state.py

@@ -226,9 +226,13 @@ class _SWITCH_CONNECT(Sentinel, metaclass=Sentinel):
     },
 }
 
+StateTransitionType = Dict[
+    Tuple[Type[Sentinel], Type[Sentinel]], Dict[Type[Sentinel], Type[Sentinel]]
+]
+
 # NB: there are also some special-case state-triggered transitions hard-coded
 # into _fire_state_triggered_transitions below.
-STATE_TRIGGERED_TRANSITIONS = {
+STATE_TRIGGERED_TRANSITIONS: StateTransitionType = {
     # (Client state, Server state) -> new states
     # Protocol negotiation
     (MIGHT_SWITCH_PROTOCOL, SWITCHED_PROTOCOL): {CLIENT: SWITCHED_PROTOCOL},
@@ -345,7 +349,7 @@ def _fire_state_triggered_transitions(self) -> None:
             # Tabular state-triggered transitions
             joint_state = (self.states[CLIENT], self.states[SERVER])
             changes = STATE_TRIGGERED_TRANSITIONS.get(joint_state, {})
-            self.states.update(changes)  # type: ignore
+            self.states.update(changes)
 
             if self.states == start_states:
                 # Fixed point reached

h11/_writers.py

@@ -125,7 +125,7 @@ def send_eom(self, headers: Headers, write: Writer) -> None:
 
 
 WritersType = Dict[
-    Union[Tuple[Sentinel, Sentinel], Sentinel],
+    Union[Tuple[Type[Sentinel], Type[Sentinel]], Type[Sentinel]],
     Union[
         Dict[str, Type[BodyWriter]],
         Callable[[Union[InformationalResponse, Response], Writer], None],