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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 deurlform_app(parser, cmd, args):
 # pragma: no cover """ decode a query string into its key value pairs. """


    parser.add_argument('value', help='the query string to decode')
    args = parser.parse_args(args)
    return ' '.join('%s=%s' % (key, value) for key, values in deurlform(args.value).items() for value in values)