

class FatalError(Exception):
    '''An error from which we cannot recover.
    '''
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)


class FatalConfigError(Exception):
    '''Something with the configuration is really bad.
    '''
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

@@ -182,33 +182,34 @@
 ConfigError(
-Exception
+FatalError
 ):%0A    '''So

Fix error hierarchy