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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 validate_answer(self, value):
 """ Check that the answer is JSON-serializable and not too long. """

        # Check that the answer is JSON-serializable
        try:
            serialized = json.dumps(value)
        except (ValueError, TypeError):
            raise serializers.ValidationError("Answer value must be JSON-serializable")

        # Check the length of the serialized representation
        if len(serialized) > Submission.MAXSIZE:
            raise serializers.ValidationError("Maximum answer size exceeded.")

        return value