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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_valid(self, value):
        ''' Whether the value passes validation

        Args:
            value (obj) : the value to validate against this property type

        Returns:
            True if valid, False otherwise

        '''
        try:
            if validation_on():
                self.validate(value, False)
        except ValueError:
            return False
        else:
            return True