Add dls_class to root of xml in generated bob files

Author: OCopping

src/techui_builder/generate.py

@@ -4,6 +4,7 @@
 from collections.abc import Mapping, Sequence
 from dataclasses import dataclass, field
 from pathlib import Path
+from xml.etree.ElementTree import SubElement
 
 import yaml
 from lxml import objectify
@@ -345,6 +346,9 @@ def build_groups(self):
         """
         # Create screen
         self.screen_ = pscreen.Screen(self.screen_name)
+        s = SubElement(self.screen_.root, "class")
+        s.text = "dls_class"
+
         # Empty widget buffer
         self.widgets = []