visitor: eliminate hidden imports

diff --git a/src/mdis/visitor.py b/src/mdis/visitor.py
index 8eb1f2219fb6fa5114d44e7de61b5d3439e6f005..ca6f80990f0e2362b5bce84bf8c69a98d79cd018 100644 (file)
--- a/src/mdis/visitor.py
+++ b/src/mdis/visitor.py
@@ -1,20 +1,26 @@
-import contextlib as _contextlib
+__all__ = [
+    "ContextVisitor",
+    "Visitor",
+    "VisitorMeta",
+]
 
-from . import dispatcher as _dispatcher
+import contextlib
 
+from . import dispatcher
 
-class VisitorMeta(_dispatcher.DispatcherMeta):
+
+class VisitorMeta(dispatcher.DispatcherMeta):
     pass
 
 
-class Visitor(_dispatcher.Dispatcher, metaclass=VisitorMeta):
-    @_dispatcher.Hook(object)
+class Visitor(dispatcher.Dispatcher, metaclass=VisitorMeta):
+    @dispatcher.Hook(object)
     def dispatch_object(self, instance):
         return instance
 
 
 class ContextVisitor(Visitor):
-    @_dispatcher.Hook(object)
-    @_contextlib.contextmanager
+    @dispatcher.Hook(object)
+    @contextlib.contextmanager
     def dispatch_object(self, instance):
         yield super().__call__(instance=instance)