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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 init_ixn(api, logger, install_dir=None):
 """ Create IXN object. :param api: tcl/python/rest :type api: trafficgenerator.tgn_utils.ApiType :param logger: logger object :param install_dir: IXN installation directory :return: IXN object """


    if api == ApiType.tcl:
        api_wrapper = IxnTclWrapper(logger, install_dir)
    elif api == ApiType.python:
        api_wrapper = IxnPythonWrapper(logger, install_dir)
    elif api == ApiType.rest:
        api_wrapper = IxnRestWrapper(logger)
    else:
        raise TgnError('{} API not supported - use Tcl, python or REST'.format(api))
    return IxnApp(logger, api_wrapper)