MAINT: refactor _Messages; passing unittest

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src/caosdb/common/models.py

@@ -2403,6 +2403,8 @@ class _Messages(list):
     (to be continued...)
     """
 
+    _is_wrapped = False
+
     def clear_server_messages(self):
         # TODO can we deprecate this and refer people to clear
         """Removes all error, warning and info messages."""
@@ -2579,6 +2581,9 @@ def donotuse(func):
 
 def _message_wrap_deprication(msg):
     """ function to allow deprecation of _Messages return values """
+    if not msg._is_wrapped:
+        return msg
+    msg._is_wrapped = True
     msg.clear_server_messages = donotuse(msg.clear_server_messages)
     msg.__setitem__ = donotuse(msg.__setitem__)
     msg.__delitem__ = donotuse(msg.__delitem__)