tests: fix AST return in TCL

tests/scripts/python/unparse.py

@@ -786,6 +786,17 @@ class UnparseTcl(UnparsePython):
         """Add an AST Pass in output."""
         pass
 
+    def _ast_return(self, node):
+        """Add an AST Return in output."""
+        self.fill('return')
+        if node.value:
+            self.add(
+                ' ',
+                (self.prefix, '$'),
+                node.value,
+                (self.prefix, None),
+            )
+
     def _ast_str(self, node):
         """Add an AST Str in output."""
         self.add('"%s"' % node.s.replace('$', '\\$'))