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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 addTrail(self, offset=None, maxlength=None, n=25, c=None, alpha=None, lw=1):
 """Add a trailing line to actor. :param offset: set an offset vector from the object center. :param maxlength: length of trailing line in absolute units :param n: number of segments to control precision :param lw: line width of the trail .. hint:: |trail| |trail.py|_ """

        if maxlength is None:
            maxlength = self.diagonalSize() * 20
            if maxlength == 0:
                maxlength = 1

        if self.trail is None:
            pos = self.GetPosition()
            self.trailPoints = [None] * n
            self.trailSegmentSize = maxlength / n
            self.trailOffset = offset

            ppoints = vtk.vtkPoints()  # Generate the polyline
            poly = vtk.vtkPolyData()
            ppoints.SetData(numpy_to_vtk([pos] * n))
            poly.SetPoints(ppoints)
            lines = vtk.vtkCellArray()
            lines.InsertNextCell(n)
            for i in range(n):
                lines.InsertCellPoint(i)
            poly.SetPoints(ppoints)
            poly.SetLines(lines)
            mapper = vtk.vtkPolyDataMapper()

            if c is None:
                if hasattr(self, "GetProperty"):
                    col = self.GetProperty().GetColor()
                else:
                    col = (0.1, 0.1, 0.1)
            else:
                col = colors.getColor(c)

            if alpha is None:
                alpha = 1
                if hasattr(self, "GetProperty"):
                    alpha = self.GetProperty().GetOpacity()

            mapper.SetInputData(poly)
            tline = Actor()
            tline.SetMapper(mapper)
            tline.GetProperty().SetColor(col)
            tline.GetProperty().SetOpacity(alpha)
            tline.GetProperty().SetLineWidth(lw)
            self.trail = tline  # holds the vtkActor
            return self