allow structure elements in conversion

src/caoscrawler/converters.py

@@ -715,7 +715,9 @@ class MarkdownFileConverter(SimpleFileConverter):
 def convert_basic_element(element: Union[list, dict, bool, int, float, str, None], name=None,
                           msg_prefix=""):
     """Convert basic Python objects to the corresponding StructureElements"""
-    if isinstance(element, list):
+    if isinstance(element, StructureElement):
+        return element
+    elif isinstance(element, list):
         return ListElement(name, element)
     elif isinstance(element, dict):
         return DictElement(name, element)
@@ -1078,7 +1080,7 @@ class ListElementConverter(Converter):
         # TODO: See comment on types and inheritance
         if not isinstance(element, ListElement):
             raise RuntimeError(
-                "This converter can only process DictListElements.")
+                "This converter can only process ListElements.")
         children: list[StructureElement] = []
         for index, list_element in enumerate(element.value):
             children.append(