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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 scatter_plot_source(self, scatter_plot_source):
 """Sets the scatter_plot_source of this ChartSourceQuery. For scatter plots, does this query source the X-axis or the Y-axis # noqa: E501 :param scatter_plot_source: The scatter_plot_source of this ChartSourceQuery. # noqa: E501 :type: str """

        allowed_values = ["X", "Y"]  # noqa: E501
        if scatter_plot_source not in allowed_values:
            raise ValueError(
                "Invalid value for `scatter_plot_source` ({0}), must be one of {1}"  # noqa: E501
                .format(scatter_plot_source, allowed_values)
            )

        self._scatter_plot_source = scatter_plot_source