Each of the OpenStack client libraries (i.e. the ``python-*client``
        projects that live under https://github.com/openstack/) has its own way
        of connecting to the identity service (keystone).

        The object returned here is a :class:`novaclient.v1_1.client.Client`.

def nova_client(self):
        """
        Each of the OpenStack client libraries (i.e. the ``python-*client``
        projects that live under https://github.com/openstack/) has its own way
        of connecting to the identity service (keystone).

        The object returned here is a :class:`novaclient.v1_1.client.Client`.

        """
        if not self._client:
            self._client = self._get_nova_client()
        return self._client