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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 variation_name(self, variation_name):
 """ Sets the variation_name of this OrderLineItem. The name of the variation applied to this line item. :param variation_name: The variation_name of this OrderLineItem. :type: str """


        if variation_name is None:
            raise ValueError("Invalid value for `variation_name`, must not be `None`")
        if len(variation_name) > 255:
            raise ValueError("Invalid value for `variation_name`, length must be less than `255`")

        self._variation_name = variation_name