move TB and Frame externs into python.lib.Sys

std/python/lib/Sys.hx

@@ -7,6 +7,9 @@ import python.lib.io.TextIOBase;
 import python.lib.Tuple.Tup3;
 import python.lib.Types;
 
+extern class TB {}
+extern class Frame {}
+
 extern class Sys {
 
 	public static var argv(default, never):Array<String>;

std/python/lib/Traceback.hx

@@ -1,12 +1,15 @@
 package python.lib;
 
+import python.lib.Sys;
+import python.lib.Sys.Frame;
 import python.lib.Types;
 import python.lib.Tuple;
 
+
 extern class Traceback {
 
 	public static function extract_stack(?f:Frame, ?limit:Int):Array<StackItem>;
-	public static function extract_tb(tb:TB, ?limit:Int):Array<StackItem>;
+	public static function extract_tb(tb:Sys.TB, ?limit:Int):Array<StackItem>;
 
 	static function __init__ ():Void {
 		python.Syntax.importAs("traceback", "python.lib.Traceback");

std/python/lib/Types.hx

@@ -10,9 +10,6 @@ abstract Choice <A,B>(Dynamic) {
 	@:from public static inline function fromB <A,B>(x:B):Choice<A,B> return cast x;
 }
 
-typedef Variant<A,B> = Dynamic;
-typedef Variant3<A,B,C> = Dynamic;
-typedef Variant4<A,B,C,D> = Dynamic;
 
 
 
@@ -35,5 +32,4 @@ typedef NativeComparable = {
 
 
 
-extern class TB {}
-extern class Frame {}
+