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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _verify(self):
 """ Verify the specified scenario was found and returns None. :return: None """

        scenario_names = [c.scenario.name for c in self._configs]
        if self._scenario_name not in scenario_names:
            msg = ("Scenario '{}' not found.  "
                   'Exiting.').format(self._scenario_name)
            util.sysexit_with_message(msg)