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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 update_resource(zone, resource_type, resource_selector, **kwargs):
    '''
    Add a resource

    zone : string
        name of zone
    resource_type : string
        type of resource
    resource_selector : string
        unique resource identifier
    kwargs : string|int|...
        resource properties

    .. note::
        Set resource_selector to None for resource that do not require one.

    CLI Example:

    .. code-block:: bash

        salt '*' zonecfg.update_resource tallgeese rctl name name=zone.max-locked-memory value='(priv=privileged,limit=33554432,action=deny)'
    '''
    return _resource('update', zone, resource_type, resource_selector, **kwargs)