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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 ExportInstance(r, instance, mode, destination, shutdown=None, remove_instance=None, x509_key_name=None, destination_x509_ca=None):
 """ Exports an instance. @type instance: string @param instance: Instance name @type mode: string @param mode: Export mode @rtype: string @return: Job ID """


    body = {
        "destination": destination,
        "mode": mode,
    }

    if shutdown is not None:
        body["shutdown"] = shutdown

    if remove_instance is not None:
        body["remove_instance"] = remove_instance

    if x509_key_name is not None:
        body["x509_key_name"] = x509_key_name

    if destination_x509_ca is not None:
        body["destination_x509_ca"] = destination_x509_ca

    return r.request("put", "/2/instances/%s/export" % instance, content=body)