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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 main():
 """ NAME plot_cdf.py DESCRIPTION makes plots of cdfs of data in input file SYNTAX plot_cdf.py [-h][command line options] OPTIONS -h prints help message and quits -f FILE -t TITLE -fmt [svg,eps,png,pdf,jpg..] specify format of output figure, default is svg -sav saves plot and quits """

    fmt,plot='svg',0
    title=""
    if '-h' in sys.argv:
        print(main.__doc__)
        sys.exit()
    if '-sav' in sys.argv:plot=1
    if '-f' in sys.argv:
       ind=sys.argv.index('-f')
       file=sys.argv[ind+1] 
       X=numpy.loadtxt(file)
#    else:
#       X=numpy.loadtxt(sys.stdin,dtype=numpy.float)
    else:
       print('-f option required')
       print(main.__doc__)
       sys.exit()
    if '-fmt' in sys.argv:
       ind=sys.argv.index('-fmt')
       fmt=sys.argv[ind+1] 
    if '-t' in sys.argv:
       ind=sys.argv.index('-t')
       title=sys.argv[ind+1] 
    CDF={'X':1}
    pmagplotlib.plot_init(CDF['X'],5,5)
    pmagplotlib.plot_cdf(CDF['X'],X,title,'r','')
    files={'X':'CDF_.'+fmt}
    if plot==0:
        pmagplotlib.draw_figs(CDF)
        ans= input('S[a]ve  plot, <Return> to quit ')
        if ans=='a':
            pmagplotlib.save_plots(CDF,files)
    else:
        pmagplotlib.save_plots(CDF,files)