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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_required(self, attributes):
 """Ensure required attributes are present."""

        required_fulfilled = set(self._required).issubset(set(attributes))
        if not required_fulfilled:
            raise ValueError(
                "Not all required attributes fulfilled. Required: {required}".format(required=set(self._required))
            )