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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(cls, id):
 """ Get the VRF with id 'id'. """


        # cached?
        if CACHE:
            if id in _cache['VRF']:
                log.debug('cache hit for VRF %d' % id)
                return _cache['VRF'][id]
            log.debug('cache miss for VRF %d' % id)

        try:
            vrf = VRF.list({ 'id': id })[0]
        except IndexError:
            raise NipapNonExistentError('no VRF with ID ' + str(id) + ' found')

        _cache['VRF'][id] = vrf
        return vrf