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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 task2ics():
 """Command line tool to convert from Taskwarrior to iCalendar"""

    from argparse import ArgumentParser, FileType
    from sys import stdout

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

    task = IcsTask(args.indir)
    args.outfile.write(task.to_vobject().serialize())