Allow nodes in shadow roots to be addressed via Element (#1454)

pyscriptjs/tests/py-unit/_pyscript_js.py

@@ -1,4 +1,10 @@
 from unittest.mock import Mock
 
+import js
+
 showWarning = Mock()
 define_custom_element = Mock()
+
+
+def deepQuerySelector(selector):
+    return js.document.querySelector(selector)