old_contents: # custom exceptions for ElasticSearch
  
  class SearchException(Exception):
      pass
  
  
  class IndexNotFoundError(SearchException):
      pass
  
  
  class MalformedQueryError(SearchException):
      pass
  
new_contents: # custom exceptions for ElasticSearch
  
  class SearchException(Exception):
      pass
  
  
  class IndexNotFoundError(SearchException):
      pass
  
  
  class MalformedQueryError(SearchException):
      pass
  
  class SearchUnavailableError(SearchException):
      pass
  
subject: Add SearchUnavailableError