<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def _get_simple(self, name):
 """ Query the stack for a non-dotted name. """

        for item in reversed(self._stack):
            result = _get_value(item, name)
            if result is not _NOT_FOUND:
                return result

        raise KeyNotFoundError(name, "part missing")