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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 system_error(self, msg_id=None, message=None, description=None, validation_timeout=False, exc_info=None, **kw):
 """Add an error message for an unexpected exception in validator code, and move it to the front of the error message list. If `exc_info` is supplied, the error will be logged. If the error is a validation timeout, it is re-raised unless `msg_id` is "validation_timeout"."""


        if exc_info:
            if (isinstance(exc_info[1], validator.ValidationTimeout) and
                    msg_id != 'validation_timeout'):
                # These should always propagate to the top-level exception
                # handler, and be reported only once.
                raise exc_info[1]

            log.error('Unexpected error during validation: %s: %s'
                      % (exc_info[0].__name__, exc_info[1]),
                      exc_info=exc_info)

        full_id = ('validator', 'unexpected_exception')
        if msg_id:
            full_id += (msg_id,)

        self.error(full_id,
                   message or 'An unexpected error has occurred.',
                   description or
                   ('Validation was unable to complete successfully due '
                    'to an unexpected error.',
                    'The error has been logged, but please consider '
                    'filing an issue report here: '
                    'https://bit.ly/1POrYYU'),
                   tier=1, **kw)

        # Move the error message to the beginning of the list.
        self.errors.insert(0, self.errors.pop())