old_contents: class PolydatumException(Exception):
      pass
  
  
  class ServiceError(PolydatumException):
      code = 500
  
  
  class NotFound(ServiceError):
      code = 404
  
  
  class ErrorsOnClose(PolydatumException):
      def __init__(self, message, exceptions):
          super(Exception, self).__init__(message)
          self.message = message
          self.exceptions = exceptions
  
      def __str__(self):
          return '<{} {}: {}>'.format(
              self.__class__.__name__,
              self.message,
              self.exceptions
          )
  
  
  class AlreadyExistsException(PolydatumException):
      """
      Service, middleware, or resource already exists
      """
  
  
  class MiddlewareException(PolydatumException):
      pass
  
  
  class MiddlewareSetupException(MiddlewareException):
      """
      Middleware setup failed
      """
  
  
  class ResourceException(PolydatumException):
      pass
  
  
  class ResourceSetupException(ResourceException):
      """
      Resource setup failed
      """
new_contents: class PolydatumException(Exception):
      pass
  
  
  class ServiceError(PolydatumException):
      code = 500
  
  
  class NotFound(ServiceError):
      code = 404
  
  
  class ErrorsOnClose(PolydatumException):
      """
      Deprecated 0.8.4 as Resources errors on exit
      are suppressed
      """
      def __init__(self, message, exceptions):
          super(Exception, self).__init__(message)
          self.message = message
          self.exceptions = exceptions
  
      def __str__(self):
          return '<{} {}: {}>'.format(
              self.__class__.__name__,
              self.message,
              self.exceptions
          )
  
  
  class AlreadyExistsException(PolydatumException):
      """
      Service, middleware, or resource already exists
      """
  
  
  class MiddlewareException(PolydatumException):
      pass
  
  
  class MiddlewareSetupException(MiddlewareException):
      """
      Middleware setup failed
      """
  
  
  class ResourceException(PolydatumException):
      pass
  
  
  class ResourceSetupException(ResourceException):
      """
      Resource setup failed
      """
subject: Add deprecation note