def _state_to_status(stateno):
"""
- convery a msg state to status
+ Convert a msg state to status
+
+ Parameters
+ ----------
+ stateno: int
+ the state of the rmr message buffer
+
+ Returns
+ -------
+ string
+ the cooresponding message state
"""
sdict = _get_mapping_dict()
return sdict.get(stateno, "UNKNOWN STATE")