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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 parse_measurements.py DESCRIPTION takes measurments file and creates specimen and instrument files SYNTAX parse_measurements.py [command line options] OPTIONS -h prints help message and quits -f FILE magic_measurements input file, default is "magic_measurements.txt" -fsi FILE er_sites input file, default is none -Fsp FILE specimen output er_specimens format file, default is "er_specimens.txt" -Fin FILE instrument output magic_instruments format file, default is "magic_instruments.txt" OUPUT writes er_specimens and magic_instruments formatted files """

    infile = 'magic_measurements.txt'
    sitefile = ""
    specout = "er_specimens.txt"
    instout = "magic_instruments.txt"
# get command line stuff
    if "-h" in sys.argv:
        print(main.__doc__)
        sys.exit()
    if '-f' in sys.argv:
        ind = sys.argv.index("-f")
        infile = sys.argv[ind + 1]
    if '-fsi' in sys.argv:
        ind = sys.argv.index("-fsi")
        sitefile = sys.argv[ind + 1]
    if '-Fsp' in sys.argv:
        ind = sys.argv.index("-Fsp")
        specout = sys.argv[ind + 1]
    if '-Fin' in sys.argv:
        ind = sys.argv.index("-Fin")
        instout = sys.argv[ind + 1]
    if '-WD' in sys.argv:
        ind = sys.argv.index("-WD")
        dir_path = sys.argv[ind + 1]
        infile = dir_path + '/' + infile
        if sitefile != "":
            sitefile = dir_path + '/' + sitefile
        specout = dir_path + '/' + specout
        instout = dir_path + '/' + instout
# now do re-ordering
    pmag.ParseMeasFile(infile, sitefile, instout, specout)