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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 _enforceDataType(self, data):
 """ Converts to str so that this CTI always stores that type. """

        qColor = QtGui.QColor(data)    # TODO: store a RGB string?
        if not qColor.isValid():
            raise ValueError("Invalid color specification: {!r}".format(data))
        return qColor