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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 draw_marked_line(self, data, coordinates, linestyle, markerstyle, label, mplobj=None):
 """Draw a line that also has markers. If this isn't reimplemented by a renderer object, by default, it will make a call to BOTH draw_line and draw_markers when both markerstyle and linestyle are not None in the same Line2D object. """

        if linestyle is not None:
            self.draw_line(data, coordinates, linestyle, label, mplobj)
        if markerstyle is not None:
            self.draw_markers(data, coordinates, markerstyle, label, mplobj)