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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 display(self, display):
 """Sets the display of this Message. The form of display for this message # noqa: E501 :param display: The display of this Message. # noqa: E501 :type: str """

        if display is None:
            raise ValueError("Invalid value for `display`, must not be `None`")  # noqa: E501
        allowed_values = ["BANNER", "TOASTER"]  # noqa: E501
        if display not in allowed_values:
            raise ValueError(
                "Invalid value for `display` ({0}), must be one of {1}"  # noqa: E501
                .format(display, allowed_values)
            )

        self._display = display