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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 command_line():
    ''' If you want to use the command line '''
    from docopt import docopt
    doc = docopt( __doc__, version=VERSION )
    args = pd.Series({k.replace('--', ''): v for k, v in doc.items()})
    if args.all:
        graph = Graph2Pandas(args.file, _type='all')
    elif args.type:
        graph = Graph2Pandas(args.file, _type=args.type)
    else:
        graph = Graph2Pandas(args.file)
    graph.save(args.output)