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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 _appendContour(self, contour, offset=None, **kwargs):
 """ contour will be an object with a drawPoints method. offset will be a valid offset (x, y). This must return the new contour. Subclasses may override this method. """

        copy = contour.copy()
        if offset != (0, 0):
            copy.moveBy(offset)
        pointPen = self.getPointPen()
        contour.drawPoints(pointPen)
        return self[-1]