fix typing

typer/core.py

@@ -739,8 +739,8 @@ def format_help(self, ctx: click.Context, formatter: click.HelpFormatter) -> Non
             markup_mode=self.rich_markup_mode,
         )
 
-    def list_commands(self, ctx: click.Context) -> list[str]:
+    def list_commands(self, ctx: click.Context) -> List[str]:
         """Returns a list of subcommand names.
-         Note that in Click's Group class, these are sorted.
-         In Typer, we wish to maintain the original order of creation (cf Issue #933)"""
-        return self.commands
+        Note that in Click's Group class, these are sorted.
+        In Typer, we wish to maintain the original order of creation (cf Issue #933)"""
+        return [n for n, c in self.commands.items()]