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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 is_fully_verified(self):
 """ Determine if this Job is fully verified based on the state of its Errors. An Error (TextLogError or FailureLine) is considered Verified once its related TextLogErrorMetadata has best_is_verified set to True. A Job is then considered Verified once all its Errors TextLogErrorMetadata instances are set to True. """

        unverified_errors = TextLogError.objects.filter(
            _metadata__best_is_verified=False,
            step__job=self).count()

        if unverified_errors:
            logger.error("Job %r has unverified TextLogErrors", self)
            return False

        logger.info("Job %r is fully verified", self)
        return True