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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 write_plot(plot, filename, width=DEFAULT_PAGE_WIDTH, height=DEFAULT_PAGE_HEIGHT, unit=DEFAULT_PAGE_UNIT):
 """Writes a plot SVG to a file. Args: plot (list):
 a list of layers to plot filename (str):
 the name of the file to write width (float):
 the width of the output SVG height (float):
 the height of the output SVG unit (str):
 the unit of the height and width """

    svg = plot_to_svg(plot, width, height, unit)
    with open(filename, 'w') as outfile:
        outfile.write(svg)