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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 get_changeset(args):
 """Dump the changeset objects as JSON, reading the provided bundle YAML. The YAML can be provided either from stdin or by passing a file path as first argument. """

    # Parse the arguments.
    parser = argparse.ArgumentParser(description=get_changeset.__doc__)
    parser.add_argument(
        'infile', nargs='?', type=argparse.FileType('r'), default=sys.stdin,
        help='path to the bundle YAML file')
    parser.add_argument(
        '--version', action='version', version='%(prog)s {}'.format(version))
    options = parser.parse_args(args)

    # Parse the provided YAML file.
    try:
        bundle = yaml.safe_load(options.infile)
    except Exception:
        return 'error: the provided bundle is not a valid YAML'

    # Validate the bundle object.
    errors = validation.validate(bundle)
    if errors:
        return '\n'.join(errors)

    # Dump the changeset to stdout.
    print('[')
    for num, change in enumerate(changeset.parse(bundle)):
        if num:
            print(',')
        print(json.dumps(change))
    print(']')