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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 ics2task():
 """Command line tool to convert from iCalendar to Taskwarrior"""

    from argparse import ArgumentParser, FileType
    from sys import stdin

    parser = ArgumentParser(description='Converter from iCalendar to Taskwarrior syntax.')
    parser.add_argument('infile', nargs='?', type=FileType('r'), default=stdin,
                        help='Input iCalendar file (default: stdin)')
    parser.add_argument('outdir', nargs='?', help='Output Taskwarrior directory (default to ~/.task)', default=expanduser('~/.task'))
    args = parser.parse_args()

    vobject = readOne(args.infile.read())
    task = IcsTask(args.outdir)
    for todo in vobject.vtodo_list:
        task.to_task(todo)