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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(self):
 """Validate the contents of the object. This calls ``setattr`` for each of the class's grammar properties. It will catch ``ValueError``s raised by the grammar property's setters and re-raise them as :class:`ValidationError`. """

        for key, val in self.grammar.items():
            try:
                setattr(self, key, val)
            except ValueError as e:
                raise ValidationError('invalid contents: ' + e.args[0])