'Unique hash for this network.
The hash is a function of an SHA1 hash of the network\'s ID and
its driver which means that it should be unique between all
networks. In some subclasses (e.g. GoGrid) there is no ID
available so the public IP address is used. This means that,
unlike a properly done system UUID, the same UUID may mean a
different system install at a different time
>>> from libcloud.network.drivers.dummy import DummyNetworkDriver
>>> driver = DummyNetworkDriver()
>>> network = driver.create_network()
>>> network.get_uuid()
\'d3748461511d8b9b0e0bfa0d4d3383a619a2bb9f\'
Note, for example, that this example will always produce the
same UUID!
:rtype:  ``str``
:return: Unique identifier for this instance.'

def get_uuid(self):

    return hashlib.sha1(b(('%s:%s' % (self.id, self.driver.type)))).hexdigest()
