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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 add_image(self, filename, *, width=NoEscape(r'\linewidth'), placement=None):
 """Add an image to the subfigure. Args ---- filename: str Filename of the image. width: str Width of the image in LaTeX terms. placement: str Placement of the figure, `None` is also accepted. """


        super().add_image(filename, width=width, placement=placement)