'List node image skus in an offer.
:param offer: The complete resource path to an offer (as returned by
`ex_list_offers`)
:type publisher: ``str``
:return: A list of tuples in the form
("sku id", "sku name")
:rtype: ``list``'

def ex_list_skus(self, offer):

    action = ('%s/skus' % offer)
    r = self.connection.request(action, params={'api-version': '2015-06-15'})
    return [(sku['id'], sku['name']) for sku in r.object]
