def delete(self, link, extras):
        if link.target.identifier == '/network/public':
            # public means floating IP in OS!
            net.remove_floating_ip(link.source.attributes['occi.core.id'],
                                   link.attributes['occi.networkinterface.'
                                                   'address'],
                                   extras['nova_ctx'])
Given a pacakge requirement this returns the information about this
dataset/ETHPy150Open tmetsch/occi-os/occi_os_api/backends/network.py/NetworkInterfaceBackend.delete--crossover with--dataset/ETHPy150Open lektor/lektor/lektor/packages.py/add_package_to_project