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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 output_json(gandi, format, value):
 """ Helper to show json output """

    if format == 'json':
        gandi.echo(json.dumps(value, default=date_handler, sort_keys=True))
    elif format == 'pretty-json':
        gandi.echo(json.dumps(value, default=date_handler, sort_keys=True,
                              indent=2, separators=(',', ': ')))